The document provides an overview of basic computer concepts including hardware, software, and how computers work. It discusses:
1. The input-process-output cycle that computers follow when processing information, with examples of how different computer components like the keyboard, monitor, and processor are involved in this cycle.
2. The main types of computer hardware including the system unit, input devices like keyboards and mice, and output devices like monitors and printers.
3. How software in the form of operating systems and application programs allows computers to perform tasks by processing input data.
4. Different types of computers categorized by size and capabilities, from microcomputers to mainframes and supercomputers.
5. How memory
The document discusses the four main parts of a computer system: hardware, software, data, and users. It defines each part and provides examples. Hardware includes processing devices like the CPU and memory devices like RAM. Software includes system software like the operating system and application software like Word. Data are pieces of information stored on the computer. Users are people who operate the computer and tell it what to do. The document also summarizes the basic steps of information processing and categories of essential computer hardware and types of software.
Components of a computer can be divided into 3 main categories: hardware, software, and brainware. Hardware includes processing devices like the CPU, as well as input devices, output devices, and storage devices. Software includes operating systems like Windows and Linux, as well as application programs and programming languages. Brainware refers to the people who operate computers. The document then provides further details about the specific components that fall under each of these three main categories.
The document discusses the four main parts of a computer system: hardware, software, data, and users. It defines each part and provides examples. Hardware includes processing devices like the CPU, memory devices like RAM and ROM, and input/output and storage devices. Software tells the computer what to do and includes system software like the operating system and application software. Data are pieces of information stored and organized by computers. Users are people who operate the computer and provide instructions on what tasks to complete.
The document discusses the four main parts of a computer system: hardware, software, data, and users. It describes hardware as the mechanical and physical components, software as programs that tell the computer what to do, data as pieces of information, and users as people operating the computer. It then provides more details on essential computer hardware components, types of software, how data is stored, and the roles of computer users.
This document discusses the four main parts of a computer system: hardware, software, data, and users. It defines each part and provides examples. Hardware includes processing devices like the CPU, memory devices like RAM and ROM, and input/output and storage devices. Software tells the hardware what to do and is divided into system software and application software. Data are pieces of information stored and organized by the computer. Users are people who operate the computer and provide instructions on what tasks it should perform.
The document discusses the four main parts of a computer system: hardware, software, data, and users. It describes the essential hardware components including processing devices like the CPU, memory devices like RAM and ROM, input/output devices, and storage devices. It also discusses the two main types of software - system software like operating systems, and application software. Finally, it briefly mentions computer data and the different roles users can play when interacting with computer systems.
The document discusses the four main parts of a computer system: hardware, software, data, and users. It describes hardware as the physical and mechanical components like processors, memory, storage, and input/output devices. Software refers to programs that tell the computer what to do, including operating systems and applications. Data is the information stored and processed by computers. Users are people who operate computers and provide input to tell the computer what tasks to perform.
The document discusses the four main parts of a computer system: hardware, software, data, and users. It defines each part and provides examples. Hardware includes processing devices like the CPU and memory devices like RAM. Software includes system software like the operating system and application software like Word. Data are pieces of information stored on the computer. Users are people who operate the computer and tell it what to do. The document also summarizes the basic steps of information processing and categories of essential computer hardware and types of software.
Components of a computer can be divided into 3 main categories: hardware, software, and brainware. Hardware includes processing devices like the CPU, as well as input devices, output devices, and storage devices. Software includes operating systems like Windows and Linux, as well as application programs and programming languages. Brainware refers to the people who operate computers. The document then provides further details about the specific components that fall under each of these three main categories.
The document discusses the four main parts of a computer system: hardware, software, data, and users. It defines each part and provides examples. Hardware includes processing devices like the CPU, memory devices like RAM and ROM, and input/output and storage devices. Software tells the computer what to do and includes system software like the operating system and application software. Data are pieces of information stored and organized by computers. Users are people who operate the computer and provide instructions on what tasks to complete.
The document discusses the four main parts of a computer system: hardware, software, data, and users. It describes hardware as the mechanical and physical components, software as programs that tell the computer what to do, data as pieces of information, and users as people operating the computer. It then provides more details on essential computer hardware components, types of software, how data is stored, and the roles of computer users.
This document discusses the four main parts of a computer system: hardware, software, data, and users. It defines each part and provides examples. Hardware includes processing devices like the CPU, memory devices like RAM and ROM, and input/output and storage devices. Software tells the hardware what to do and is divided into system software and application software. Data are pieces of information stored and organized by the computer. Users are people who operate the computer and provide instructions on what tasks it should perform.
The document discusses the four main parts of a computer system: hardware, software, data, and users. It describes the essential hardware components including processing devices like the CPU, memory devices like RAM and ROM, input/output devices, and storage devices. It also discusses the two main types of software - system software like operating systems, and application software. Finally, it briefly mentions computer data and the different roles users can play when interacting with computer systems.
The document discusses the four main parts of a computer system: hardware, software, data, and users. It describes hardware as the physical and mechanical components like processors, memory, storage, and input/output devices. Software refers to programs that tell the computer what to do, including operating systems and applications. Data is the information stored and processed by computers. Users are people who operate computers and provide input to tell the computer what tasks to perform.
This document provides an overview of the basic components and functions of a computer system. It discusses that a computer system consists of hardware, software, data, and users. The hardware includes processing devices like the CPU, memory devices like RAM and ROM, and input/output and storage devices. Software tells the computer what to do and includes operating systems, utility programs, and applications. Data are pieces of information stored and organized in files. Users are people who operate the computer and provide instructions.
The document discusses computer hardware, software, and input devices. It describes the four main parts of a computer system as the hardware, software, data, and users. The hardware is divided into processors, memory, input/output devices, and storage. Common input devices include keyboards and mice. Keyboards allow text entry while mice allow pointer positioning. Variants of mice include trackballs and trackpads. The document emphasizes ergonomics and proper techniques for using input devices to avoid repetitive strain injuries.
This document provides an introduction to computers including what a computer is, what it can do, its capabilities and limitations. It describes the basic parts of a computer system including hardware, software, data and users. It discusses the central processing unit, memory, input devices like keyboards and mice, output devices like monitors and printers, and storage devices like hard disks and floppy disks. It also provides an overview of computer software including operating systems and common application software like word processing, spreadsheets, presentations and databases.
This document introduces computers and their basic components. It defines a computer as an electronic device that processes data. The four main parts of a computer system are hardware, software, data, and people. Hardware refers to the physical parts of the computer, software contains the computer's instructions, data is the raw facts manipulated by the computer, and people are the users. The document outlines the four types of computer hardware, two categories of software and their purposes, and four common types of computers and the jobs they perform best.
The document provides an overview of computers, including their components and functions. It discusses how computers input, process, output and store data. It describes the basic internal and external hardware components, as well as system and application software. The document also outlines different types of computers from supercomputers to laptops. It discusses the importance of computers in modern life and for education in South Africa.
The document discusses the four main parts of a computer system: hardware, software, data, and users. It provides details on each part: hardware includes mechanical and physical components, software includes programs that tell the computer what to do, data refers to raw facts and information is processed data, and users are people who operate the computer system. The document also covers the basic computer hardware components, including processing devices like the CPU, memory devices like RAM and ROM, input/output devices, and storage devices. It discusses the two main types of software - system software like operating systems, and application software that accomplishes specific tasks. Finally, it notes that data is stored using binary and can be organized into files, and that computer users
This document provides an overview of computers and their uses. It defines computers as electronic devices that convert data into information using binary digits. It describes different types of computers including desktops, workstations, notebooks, tablets, handheld devices, and smartphones that are used by individuals. It also outlines computer types for organizations like network servers, mainframes, minicomputers, and supercomputers. Finally, it discusses the large impact of computers in society and how they are used in education, business, industry, government, and healthcare.
A computer is a combination of hardware and software that processes data into information. Computer hardware refers to the physical components like monitors, keyboards, and speakers. Computer software includes programs like Word and Excel that tell the computer what to do. A computer takes in data as input, processes it, and produces output. It has four main functional components - input, processing, output, and storage. Computers are now used in many fields like banking, education, hospitals and more due to their speed, large storage capacity, accuracy, reliability, and versatility. However, computers lack decision-making ability and have zero intelligence of their own.
The operating system is the most important program that runs on a computer and allows other programs to run. It performs basic tasks like managing input/output, files and directories, and peripheral devices. For large systems, the operating system also ensures different programs and users do not interfere with each other and is responsible for security. Operating systems provide a user interface, run programs, manage hardware devices, and organize file storage. Common types include real-time, single-tasking, multitasking, and multi-user systems.
The document discusses how computers process data. It explains that data are raw facts while information is meaningful data. Computers represent data using binary numbers for simplicity and accuracy. The CPU, which contains a control unit and arithmetic logic unit, processes data. The control unit directs data flow while the ALU performs calculations. RAM and ROM are types of memory that differ in volatility and speed of access. Processor speed and number of transistors impact processing speed. Major CPU manufacturers include Intel, Motorola, and AMD.
This document discusses different types of computers and their uses. It describes computers for individual use like desktops, notebooks, tablets, and smartphones. Computers for organizations are discussed, including network servers, mainframes, minicomputers, and supercomputers. The document also summarizes the impact of computers in society and how they are used for business, education, communication, entertainment and more. Computers have revolutionized industries like healthcare, government and small business.
chapter 1 peter norton introduction to computersM Malik
This chapter introduces computers and their basic components. It defines a computer as an electronic device that processes data. A computer system has four main parts: hardware, software, data, and people. Hardware refers to the physical parts of the computer like the processor, memory, storage, and input/output devices. Software includes the programs or instructions that make the hardware work, divided into system software and application software. The chapter lists five professions where computers are commonly used and how they have changed people's work. It also outlines the four main types of computers and what tasks each performs best.
A computer is an electronic device that receives input, processes data using programs, and produces output. It consists of hardware components like the processor, memory, and storage as well as software programs. The processor contains a control unit, arithmetic logic unit, and registers to execute instructions and perform calculations, while memory temporarily stores running programs and data and permanent storage like hard disks are used for long term file storage.
The document discusses the four main parts of a computer system: hardware, software, data, and users. It describes the essential hardware components including processing devices like the CPU, memory devices like RAM and ROM, and input/output and storage devices. It explains that software tells the computer what to do and describes the two main types: system software like the operating system, and application software that performs tasks. It also defines computer data as stored facts and describes how users interact with and manage the system.
This document provides an introduction to computers. It defines a computer as an electronic device that processes data. It then lists the four main parts of a computer system as hardware, software, data, and people. It describes the two main types of software as system software and application software, and lists examples of each. Finally, it outlines the four most common types of computers as supercomputers, mainframes, minicomputers, and microcomputers, describing the kind of jobs each does best.
This document defines hardware and software, describes categories of each, and provides examples of common hardware and software components. It defines hardware as physical computer components like keyboards and monitors, and software as programs that operate computers. The document categorizes hardware into input, output, storage, processing, and connection devices. It describes two main types of software: application software for specific tasks, and system software like operating systems and utilities. The document also lists common computer sizes from PDAs to mainframes and provides examples of input, output, storage, and connection devices.
This document defines hardware and software, describes categories of each, and provides examples of common hardware and software components. It defines hardware as physical computer components like keyboards and monitors, and software as programs that operate computers. The document categorizes hardware into input, output, storage, processing, and connection devices. It describes two main types of software: application software for specific tasks, and system software like operating systems that support applications and hardware. Finally, it provides examples of common hardware components, like printers and disk drives, and software, like operating systems and web browsers.
This document provides an overview of basic computer hardware and software components. It describes input devices like keyboards and mice, output devices like monitors and printers, the central processing unit (CPU) and its functions. It also discusses data storage devices, computer memory, graphic user interfaces, video cards, ports, resolution, networking, file management, and other key concepts. The goal is to explain the essential building blocks and functions that make up a basic computer system.
This document defines and describes computers and their components. It begins by defining a computer as a device that accepts digital data as input and processes it according to stored instructions. It then categorizes different types of computers and describes their typical uses. The rest of the document discusses the key components of a computer system, including hardware components like CPUs, memory, storage devices, and input/output devices. It also discusses software components like operating systems, applications, and system utilities. Overall, the document provides a comprehensive overview of computers and their basic anatomy and functionality.
This document provides an overview of the basic components and functions of a computer system. It discusses that a computer system consists of hardware, software, data, and users. The hardware includes processing devices like the CPU, memory devices like RAM and ROM, and input/output and storage devices. Software tells the computer what to do and includes operating systems, utility programs, and applications. Data are pieces of information stored and organized in files. Users are people who operate the computer and provide instructions.
The document discusses computer hardware, software, and input devices. It describes the four main parts of a computer system as the hardware, software, data, and users. The hardware is divided into processors, memory, input/output devices, and storage. Common input devices include keyboards and mice. Keyboards allow text entry while mice allow pointer positioning. Variants of mice include trackballs and trackpads. The document emphasizes ergonomics and proper techniques for using input devices to avoid repetitive strain injuries.
This document provides an introduction to computers including what a computer is, what it can do, its capabilities and limitations. It describes the basic parts of a computer system including hardware, software, data and users. It discusses the central processing unit, memory, input devices like keyboards and mice, output devices like monitors and printers, and storage devices like hard disks and floppy disks. It also provides an overview of computer software including operating systems and common application software like word processing, spreadsheets, presentations and databases.
This document introduces computers and their basic components. It defines a computer as an electronic device that processes data. The four main parts of a computer system are hardware, software, data, and people. Hardware refers to the physical parts of the computer, software contains the computer's instructions, data is the raw facts manipulated by the computer, and people are the users. The document outlines the four types of computer hardware, two categories of software and their purposes, and four common types of computers and the jobs they perform best.
The document provides an overview of computers, including their components and functions. It discusses how computers input, process, output and store data. It describes the basic internal and external hardware components, as well as system and application software. The document also outlines different types of computers from supercomputers to laptops. It discusses the importance of computers in modern life and for education in South Africa.
The document discusses the four main parts of a computer system: hardware, software, data, and users. It provides details on each part: hardware includes mechanical and physical components, software includes programs that tell the computer what to do, data refers to raw facts and information is processed data, and users are people who operate the computer system. The document also covers the basic computer hardware components, including processing devices like the CPU, memory devices like RAM and ROM, input/output devices, and storage devices. It discusses the two main types of software - system software like operating systems, and application software that accomplishes specific tasks. Finally, it notes that data is stored using binary and can be organized into files, and that computer users
This document provides an overview of computers and their uses. It defines computers as electronic devices that convert data into information using binary digits. It describes different types of computers including desktops, workstations, notebooks, tablets, handheld devices, and smartphones that are used by individuals. It also outlines computer types for organizations like network servers, mainframes, minicomputers, and supercomputers. Finally, it discusses the large impact of computers in society and how they are used in education, business, industry, government, and healthcare.
A computer is a combination of hardware and software that processes data into information. Computer hardware refers to the physical components like monitors, keyboards, and speakers. Computer software includes programs like Word and Excel that tell the computer what to do. A computer takes in data as input, processes it, and produces output. It has four main functional components - input, processing, output, and storage. Computers are now used in many fields like banking, education, hospitals and more due to their speed, large storage capacity, accuracy, reliability, and versatility. However, computers lack decision-making ability and have zero intelligence of their own.
The operating system is the most important program that runs on a computer and allows other programs to run. It performs basic tasks like managing input/output, files and directories, and peripheral devices. For large systems, the operating system also ensures different programs and users do not interfere with each other and is responsible for security. Operating systems provide a user interface, run programs, manage hardware devices, and organize file storage. Common types include real-time, single-tasking, multitasking, and multi-user systems.
The document discusses how computers process data. It explains that data are raw facts while information is meaningful data. Computers represent data using binary numbers for simplicity and accuracy. The CPU, which contains a control unit and arithmetic logic unit, processes data. The control unit directs data flow while the ALU performs calculations. RAM and ROM are types of memory that differ in volatility and speed of access. Processor speed and number of transistors impact processing speed. Major CPU manufacturers include Intel, Motorola, and AMD.
This document discusses different types of computers and their uses. It describes computers for individual use like desktops, notebooks, tablets, and smartphones. Computers for organizations are discussed, including network servers, mainframes, minicomputers, and supercomputers. The document also summarizes the impact of computers in society and how they are used for business, education, communication, entertainment and more. Computers have revolutionized industries like healthcare, government and small business.
chapter 1 peter norton introduction to computersM Malik
This chapter introduces computers and their basic components. It defines a computer as an electronic device that processes data. A computer system has four main parts: hardware, software, data, and people. Hardware refers to the physical parts of the computer like the processor, memory, storage, and input/output devices. Software includes the programs or instructions that make the hardware work, divided into system software and application software. The chapter lists five professions where computers are commonly used and how they have changed people's work. It also outlines the four main types of computers and what tasks each performs best.
A computer is an electronic device that receives input, processes data using programs, and produces output. It consists of hardware components like the processor, memory, and storage as well as software programs. The processor contains a control unit, arithmetic logic unit, and registers to execute instructions and perform calculations, while memory temporarily stores running programs and data and permanent storage like hard disks are used for long term file storage.
The document discusses the four main parts of a computer system: hardware, software, data, and users. It describes the essential hardware components including processing devices like the CPU, memory devices like RAM and ROM, and input/output and storage devices. It explains that software tells the computer what to do and describes the two main types: system software like the operating system, and application software that performs tasks. It also defines computer data as stored facts and describes how users interact with and manage the system.
This document provides an introduction to computers. It defines a computer as an electronic device that processes data. It then lists the four main parts of a computer system as hardware, software, data, and people. It describes the two main types of software as system software and application software, and lists examples of each. Finally, it outlines the four most common types of computers as supercomputers, mainframes, minicomputers, and microcomputers, describing the kind of jobs each does best.
This document defines hardware and software, describes categories of each, and provides examples of common hardware and software components. It defines hardware as physical computer components like keyboards and monitors, and software as programs that operate computers. The document categorizes hardware into input, output, storage, processing, and connection devices. It describes two main types of software: application software for specific tasks, and system software like operating systems and utilities. The document also lists common computer sizes from PDAs to mainframes and provides examples of input, output, storage, and connection devices.
This document defines hardware and software, describes categories of each, and provides examples of common hardware and software components. It defines hardware as physical computer components like keyboards and monitors, and software as programs that operate computers. The document categorizes hardware into input, output, storage, processing, and connection devices. It describes two main types of software: application software for specific tasks, and system software like operating systems that support applications and hardware. Finally, it provides examples of common hardware components, like printers and disk drives, and software, like operating systems and web browsers.
This document provides an overview of basic computer hardware and software components. It describes input devices like keyboards and mice, output devices like monitors and printers, the central processing unit (CPU) and its functions. It also discusses data storage devices, computer memory, graphic user interfaces, video cards, ports, resolution, networking, file management, and other key concepts. The goal is to explain the essential building blocks and functions that make up a basic computer system.
This document defines and describes computers and their components. It begins by defining a computer as a device that accepts digital data as input and processes it according to stored instructions. It then categorizes different types of computers and describes their typical uses. The rest of the document discusses the key components of a computer system, including hardware components like CPUs, memory, storage devices, and input/output devices. It also discusses software components like operating systems, applications, and system utilities. Overall, the document provides a comprehensive overview of computers and their basic anatomy and functionality.
This document provides an overview of computer hardware and software. It defines hardware as the physical components of a computer and lists common internal hardware like the CPU, motherboard, RAM and ROM. It also describes input devices like the keyboard and mouse, output devices like monitors and printers, and connecting hardware. The document then defines software as the set of instructions that allows hardware to function and categorizes system software, application software, programming software and utility software.
Computer is an electronic device that processes data according to programmed instructions. It has hardware components that can be seen like input devices to enter data, output devices to display processed information, processing devices to execute instructions on data, and storage devices to store data. It also uses software programs installed on the hardware to perform specific tasks, including system software to manage the hardware, application software to perform user-oriented tasks, and utility software provided by vendors to perform common functions.
This document provides an overview of basic computer hardware and software components. It describes input devices like keyboards and mice, as well as output devices like monitors and printers. It explains the central processing unit and computer chips. Data storage devices covered include hard drives, CD-ROMs, floppy disks, and flash drives. Computer memory, graphic user interfaces, video cards, ports, and peripherals are also summarized. The document concludes with sections on file management and networking concepts.
The document discusses the different types of hardware and software components that make up a computer system. It describes input devices like keyboards and mice that allow users to input data. It covers output devices like monitors and printers that display or print the output. It also discusses the central processing unit and memory that process data in the system unit. Storage devices like hard drives, USBs and CDs are explained for permanent storage. Communication devices allow computers to connect and exchange information. The document ends by distinguishing system software, like operating systems, from application software used by users to perform tasks.
The document summarizes key points from a lecture on Boolean algebra:
- It discusses theorems and rules in Boolean algebra, including DeMorgan's Theorems, and the universality of NAND and NOR gates.
- Specific topics covered include the commutative, associative, and distributive laws, truth tables, and examples applying Boolean algebra rules and identities to simplify expressions.
- DeMorgan's Theorems allow the exchange of ANDs and ORs by inverting variables, and are useful in digital circuit design.
The document provides an overview of basic computer hardware and software. It describes the central processing unit as the "brain" of the computer and lists common brands of processors. It also discusses various input and output devices, data storage technologies like hard drives, CDs, floppy disks and flash drives. The document differentiates between system software like operating systems and utilities, and application software for tasks like word processing, spreadsheets, presentations and databases.
Difference between hardware and software computer hardware vs softwareSwapan Das
This document discusses the difference between computer hardware and software. Computer hardware refers to the physical devices that can be seen and touched, such as a monitor, keyboard, mouse, and storage devices. Computer software refers to sets of instructions and code that tell the computer hardware how to perform tasks; software cannot usually be seen or touched. Some key differences are that hardware can fail over time due to wear, while software failures tend to be due to bugs and can be fixed; hardware is physical while software is logical; and hardware is used to run software programs.
Boolean algebra and logic circuits were introduced. Boolean algebra uses binary numbers (0,1) and logical operations like AND, OR, and NOT to simplify logic expressions. Basic logic gates like AND, OR, and NOT were explained. Logic circuits can be built using combinations of logic gates to perform complex logical functions. Boolean algebra is used to simplify logic circuits and increase the efficiency of digital devices like computers.
There are several types of computer networks:
- Local area networks (LANs) connect devices within a small geographic area like a home or office using technologies like Ethernet or WiFi.
- Metropolitan area networks (MANs) connect devices within a city using technologies like DSL or cable.
- Wide area networks (MANs) connect LANs over long distances using technologies like leased phone lines or satellites.
The document discusses different types of computer networks including local area networks (LANs), metropolitan area networks (MANs), and wide area networks (WANs). LANs connect devices within a limited geographic area like a home, office, or building. MANs connect LANs within a city or town. WANs connect LANs across a large geographic area like a city, country, or globally using various communication technologies. Examples of LAN configurations include a simple connection between two computers and a home network connecting devices in a residence. Examples of WAN configurations include enterprise private networks and virtual private networks.
1. Boolean algebra is a mathematical system used to specify and transform logic functions. It uses binary variables that take on values of 1 or 0 and logical operators like AND, OR, and NOT.
2. Logic gates implement logic functions physically using electronic components. Common gates are AND, OR, and NOT. Gates have a small but nonzero delay between input change and output change.
3. Boolean expressions can be represented using truth tables, logic diagrams, or algebraic expressions. Standard forms include sum-of-minterms and product-of-maxterms forms.
- Boolean algebra uses binary values (1/0) to represent true/false in digital circuits.
- The basic Boolean operations are AND, OR, and NOT. Truth tables and Boolean expressions can both be used to represent the functions of circuits.
- Boolean expressions can be simplified using algebraic rules like commutative, distributive, DeMorgan's, and absorption laws. This allows simpler circuit implementations.
There are eight main types of computer networks: LAN, WLAN, WAN, MAN, SAN, CAN, PAN, and DAN. LAN connects devices within a short area like homes or offices. WAN covers long distances to connect computers globally, with the Internet as an example. WLAN is a wireless LAN that connects devices using radio signals instead of wires. Different network types serve various purposes at different scales from personal to worldwide.
This document discusses Boolean algebra and its applications in logic gates and circuits. It begins by defining Boolean algebra as the logic used to describe propositions that are either true or false. It then provides the common logic gate symbols and their meanings. The remainder of the document walks through examples of using Boolean algebra to represent circuits with logic gates, derive the outputs of gates from given inputs, and construct circuits based on truth tables. It concludes with examples of real-world situations that can be modeled with Boolean logic.
Computer networking allows sharing of information and resources through different types of networks. The three major types are local area networks (LANs), which connect computers in a limited area like a home or office; wide area networks (WANs), which span large geographical areas like countries and connect smaller networks; and metropolitan area networks (MANs), which interconnect users in a region larger than a LAN but smaller than a WAN. Other network types discussed include personal area networks (PANs) around an individual, home networks (HANs) within a home, and enterprise private networks connecting company offices securely.
This document provides an overview of Boolean algebra and logic gates. It introduces Boolean logic operations like AND, OR, and NOT. It covers Boolean algebra laws and De Morgan's theorems. It also discusses logic gate types like AND, OR, NOT, NAND, NOR, XOR and XNOR. Karnaugh maps are introduced as a method to simplify Boolean expressions.
Digital logic gates and Boolean algebraSARITHA REDDY
The document discusses digital logic gates and Boolean algebra. It defines logic gates as electronic circuits that make logic decisions. Common logic gates include OR, AND, and NOT gates. Boolean algebra uses truth values of 0 and 1 instead of numbers, and has fundamental laws and operations for AND, OR, and NOT. Boolean algebra can be used to simplify logical expressions and save gates in digital circuit design.
Boolean algebra was developed by George Boole and applied to electrical circuits by Claude Shannon. It uses logical operators like AND, OR, and NOT to represent logical statements that are either true or false. Boolean algebra represents the states of electrical components like switches that are either open or closed. Circuits with switches in series represent AND operations, while circuits with switches in parallel represent OR operations. Boolean algebra expresses logical relationships using variables, operators, and equations in sum-of-products or product-of-sums form. It provides a mathematical foundation for analyzing electrical circuits and digital logic.
The document discusses computer hardware and software concepts. It provides examples of how computers were used to quickly retrieve life-saving medical information for a pregnant woman. Computers can process large amounts of information fast and accurately. The document then discusses different types of computers based on size and performance, including microcomputers, personal computers, mini computers, mainframes, and supercomputers. It also distinguishes between general purpose and special purpose computers. The input-process-output model is used to explain how computers work by taking the example of an airline reservation system. Key computer hardware components like the CPU, keyboard, display and printer are mapped to this model. The document concludes by defining computer hardware as the physical parts and computer software as the set
This document provides an overview of basic computer concepts, including hardware, software, and how computers work. It discusses the input-process-output cycle and how each component of a computer system relates to this. The main components are described in detail, including the keyboard, mouse, system unit, storage devices, and different types of software like application and system software. Computers are categorized based on their size and capabilities. The document aims to explain computers and their uses to those without technical backgrounds.
This document provides an overview of fundamentals of computers. It begins with an introduction defining a computer and its key characteristics of speed, accuracy, diligence, versatility, reliability, automation, and memory. It then discusses capabilities such as increasing productivity, understanding data, connecting people, facilitating learning, and making money. The document also covers limitations including lack of intelligence, decision making, common sense, and human dependency. It concludes with uses of computers in fields like education, industry, banking, entertainment, and robotics.
The document provides an introduction to computers, including definitions, comparisons to human abilities and limitations, and classifications. It defines a computer as an electronic device that can perform mathematical, logical and graphical manipulations by receiving input, processing data according to instructions, and providing output. Computers are classified by their processing type (analog, digital, hybrid), purpose (special purpose, general purpose), and physical attributes (mainframes, supercomputers, mini computers, microcomputers). The document also briefly discusses the history of computing from the abacus to modern generations of computers.
This document provides an overview of basics of computers. It discusses that computers are now integral parts of our lives and are used for various purposes like reservations, payments, banking, research etc. It then defines a computer as an electronic device that accepts data as input, processes it, and provides the output. It also discusses the characteristics of computers like speed, accuracy, storage capability. The document further explains the different types of computers like digital, analog and different generations of computers from first to fifth generation. It also classifies computers as microcomputers, minicomputers, mainframes and supercomputers. Finally, it describes the basic components and concepts of a computer system.
This document discusses why studying computers is important and provides an overview of computer hardware, software, data, and users. It notes that studying computers provides skills that are useful in many aspects of life and improves employment prospects. It then defines key computer components like the CPU, memory, storage, input and output devices. It also explains the basic functions of hardware, software, data, and how users interact with the system.
This document provides an introduction to computers, including definitions, components, and functions. It discusses the central processing unit, memory/storage units, input/output units, and various software programs. The key points covered are:
- A computer is defined as an electronic device that processes data under program instructions.
- The main components are the CPU, memory, input, and output units. The CPU contains the arithmetic logic unit and control unit.
- Memory can be internal RAM/ROM or external magnetic disks, tapes, CDs, etc.
- Common input devices are the keyboard, mouse, and scanner. Output devices include the monitor and printers.
- Software includes operating systems like Windows/DOS and productivity
This document provides an introduction to computers and their components. It defines a computer as an electronic device that accepts user input, processes it, produces output, and stores results. The main components of a computer are described as the central processing unit (CPU), memory unit, and input/output devices. The CPU is said to be the brain and control center, and has three main components - the control unit, arithmetic logic unit, and memory unit. The control unit controls all computer activities and processes, while the ALU performs arithmetic and logical operations on data. The memory unit is the computer's storage and comes in primary and secondary types.
This document defines computers and describes their capabilities and limitations. It discusses that computers are everywhere and have become essential tools in homes, schools and offices. It then defines computers as programmable electronic devices that can store, retrieve and process data according to instructions. The document outlines different types of computers based on size and power, from supercomputers to mainframes, minicomputers and microcomputers like personal computers. While computers can perform repetitive tasks at high speeds and with accuracy, they are still limited and cannot match human abilities such as creative writing. The core functions of computers are described as receiving input, processing information, producing output, and storing data.
The document provides an overview of computers and their components and applications. It discusses:
1. The definition of a computer, its basic functions of input, processing, output, and storage.
2. Common input and output devices like keyboards, mice, monitors, and printers.
3. The three main components of a computer system - the input, central processing, and output units.
4. Widespread applications of computers in various fields like education, business, healthcare, entertainment and more.
Introduction to Computer and Generations of Computer by Er. Kamlesh TripathiLEALucknow
The document provides an introduction to computers including their history, components, and generations. It can be summarized as follows:
1) Computers have evolved from early counting tools to modern electronic devices. The first computers used vacuum tubes and were very large, expensive, and unreliable.
2) Modern computers are made up of five basic components - input, output, storage, CPU, and control unit. The CPU carries out processing using the ALU and control unit to manage data and instructions.
3) There have been five generations of computers based on the underlying technology. Each generation saw improvements in size, cost, reliability and capabilities as technologies advanced from vacuum tubes to integrated circuits, microprocessors, and beyond.
This document provides information about computers, including their uses, characteristics, classifications, and generations. It discusses how computers are used in various sectors like business, science, government, healthcare, education, and more. It describes the key characteristics of computers like speed, accuracy, diligence, versatility, reliability, automation, and memory. It classifies computers based on size, functionality, data handling, and data generation. It also outlines the five generations of computers from vacuum tubes to today's artificial intelligence-based devices. Finally, it discusses types of computers like supercomputers, mainframe computers, and mini computers.
This document provides an introduction to information and communication technology (ICT). It discusses how ICT has become an important part of modern society and is used across many fields like education, banking, transportation, medicine, and engineering. It then provides an overview of computers, including their basic parts and anatomy. It describes how computers process and store data accurately and quickly. Finally, it explains that computers need instructions in the form of software and input from users to perform tasks and produce output.
This document outlines classroom policies for a computer lab class:
1. Students are responsible for their assigned workstations and must arrive on time, stay on task, and not eat, drink, or chew gum in the lab.
2. Students will be marked tardy if not seated when the tardy bell rings and must address personal needs before or after class.
3. Students must respect peers and teachers and refrain from profanity, offensive comments or behavior, and non-authorized cell phone or electronic device use during class. Talking, singing, or walking around without permission is also prohibited.
The document provides information about a lecturer named Zaipul Anwar Bin Zainu din who teaches at the Institute of Product Design & Manufacturing, Universiti Kuala Lumpur. It includes details about the lecturer's contact information, subjects taught, course objectives and assessments, and an introduction to basic computer hardware, software, and networking topics covered in the course.
This document provides information about computers. It defines a computer as an electronic device that processes data using input, storage, processing, and output units. It then discusses different types of computers including analog, digital, supercomputers, mainframes, minicomputers, and microcomputers. Hybrid computers that have both analog and digital components are also mentioned. Input devices, storage, processors, and output are described. Characteristics like speed, accuracy, storage capacity, versatility and automation are listed for computers.
This document provides an overview of computers including:
- A computer is an electronic device that processes data into useful information. It includes hardware, software, data, and users.
- Computers can be classified based on their processing capabilities as supercomputers, mainframes, minicomputers, microcomputers, and wearables. They can also be classified as analog, digital, or hybrid based on their input/output signals.
- General purpose computers can solve many types of problems, while special purpose computers are designed to solve specific problems through dedicated programming. Servers are computers designed to share resources over a network.
The document provides information about computers and their basic components. It states that a computer is an electronic device that can accept data as input, process it according to stored instructions, produce output, and store information for future use. The basic parts of a computer are the input unit, output unit, control unit, arithmetic logic unit, and memory. The input unit allows data and instructions to be entered, the output unit provides information to the user, the control unit controls all functions, the arithmetic logic unit performs calculations, and memory stores programs and data. Hardware refers to the physical and tangible parts of a computer while software refers to the instructions that tell the computer what to do.
Classification of Computers ; Computers Impact on SocietyMDAZIZULHAKIMSHIAM
In this slide, I have discussed about the classifications of computer such as digital computer, analog computer, hybrid computer. And I have also discussed about the impact of computer on our society.
The C preprocessor performs preprocessing tasks like file inclusion, macro definition, and conditional compilation before actual compilation. It has six phases including edit, preprocess, compile, link, load, and execute. Preprocessor directives begin with # and are used to include other files, define symbolic constants and macros, and conditionally compile code and other preprocessor directives. The #define directive defines symbolic constants by replacing an identifier with text. Conditional compilation with #if controls whether code or other preprocessor directives are executed or compiled.
The document discusses dynamic memory allocation in C. It describes the four main functions for dynamic allocation - malloc(), calloc(), free(), and realloc(). malloc() allocates a block of memory of a specified size and returns a pointer. calloc() allocates multiple blocks of memory and initializes them to zero. free() releases previously allocated memory. realloc() changes the size of previously allocated memory. The document provides examples of using each function.
Files allow data to be permanently stored and accessed by programs. Basic file operations include opening, reading, writing, and closing files. To open a file, its name and access mode are passed to the fopen function, which returns a file pointer used for subsequent read/write operations. Characters can be read from and written to files using functions like getc and putc. Command line arguments passed when a program launches are accessible through the argc and argv parameters of the main function.
1. The document discusses pointers in C including declaring and initializing pointer variables, pointer operators like & and *, calling functions by reference using pointers, pointer arithmetic, and the relationship between pointers and arrays.
2. Key topics covered include using pointers to simulate call-by-reference, dereferencing pointers with *, taking addresses of variables with &, and implementing a bubble sort using pointers passed as arguments.
3. Pointer arithmetic allows incrementing, decrementing, adding/subtracting integers to pointers, and comparing pointers.
Union allows different data types to share the same memory location, but can hold the value of only one member at a time. The total memory allocated is equal to the size of the largest member. An example shows a union with members percent and grade, where assigning a float to percent and then character to grade both use the same memory location but overwrite each other. Enumerated data types define symbolic constants for integer values starting from zero, such as an enum defining colors red, yellow and green as constants 0, 1 and 2 respectively.
Structures allow grouping of heterogeneous data types into a single unit called a structure. Structures can contain integer, float, double, character data and arrays. Structures are accessed using the dot operator. Unions share the same memory location for different data types and can hold data of only one member at a time. Enumerated data types define user-defined data types using the enum keyword where symbolic constants take on integer values starting from zero.
Arrays are collections of homogeneous data that can be accessed by index position. Arrays allow storing of multiple similar data types together, start indexing at 0, and can have more than one dimension. Common string functions include strlen to find string length, strrev to reverse a string, strcat to concatenate strings, strcpy to copy strings, and strcmp and strcmpi to compare strings with and without case sensitivity.
This document discusses functions in C including syntax, declaration, definition, calling functions, actual and formal parameters, call by value, call by reference, and the difference between call by value and call by reference. It explains that functions allow breaking programs into smaller, reusable pieces of code. Parameters passed by value are copied so changes within the function don't affect the original variable, while parameters passed by reference use the address of the original variable so any changes made within the function also change the variable outside the function.
This document discusses functions in C including syntax, declaration, definition, calling functions, actual and formal parameters, call by value, call by reference, and the difference between call by value and call by reference. It explains that functions allow breaking programs into smaller, reusable pieces of code. Parameters passed by value are copied so changes within the function don't affect the original variable, while parameters passed by reference use the address of the original variable so any changes made within the function also change the variable outside the function.
This document discusses functions in C including syntax, declaration, definition, calling functions, actual and formal parameters, call by value, call by reference, and the difference between call by value and call by reference. It explains that functions allow breaking programs into smaller, reusable pieces of code. Parameters passed by value are copied so changes within the function don't affect the original variable, while parameters passed by reference use the address of the original variable so any changes made within the function also change the variable outside the function.
The document discusses different types of loops in programming - for loops, while loops, and do-while loops. For loops use an initialization, condition, and increment statement to iterate through a code block a set number of times. While loops continuously execute a code block as long as a condition remains true. Do-while loops are similar to while loops but execute the code block at least once even if the condition is false. Examples are provided to demonstrate each type of loop printing out numbers from 10 to 1.
The document discusses different types of control constructs in programming. There are two main types: decision making statements and looping statements. Decision making statements include if, if-else, and nested if-else statements which allow for conditional execution of code. Looping statements like for, while, and do-while loops allow code to repeat execution for a set number of iterations or as long as a condition remains true. Examples are provided for each type of control construct.
The document discusses various C operators including:
1) Arithmetic operators for addition, subtraction, multiplication, division, and modulus
2) Relational operators for comparisons like less than, greater than, equal to
3) Logical operators for AND, OR, and NOT operations
4) Assignment, increment, decrement, conditional, bitwise, and special operators and their uses. Examples are provided to demonstrate how each operator works.
The document discusses different types of operators in C programming including arithmetic, relational, logical, bitwise, assignment, compound assignment, shift, increment, and decrement operators. Examples are provided to demonstrate the use of arithmetic, relational, and logical operators. The increment and decrement operators ++ and -- are also explained, distinguishing between pre-increment/decrement and post-increment/decrement.
This document discusses input and output in C programming. It explains that scanf("%d",&a) is used to input an integer value from the user and store it in the variable a. It also notes that printf("%d",a) prints the value of variable a to the screen.
There are three categories of data types: primitive, derived, and user defined. Primitive types include basic types like int, float, and char. Derived types include arrays, which can contain collections of other data types. User defined types are structures and enums.
Identifiers are user-defined names for variables, functions, and arrays that are commonly in lower case. Constants have fixed values that don't change during program execution and include numeric and character constants. Character constants use escape sequences, which are special character combinations like '\n' for newline, that each represent a single character. There are 12 common escape sequences including '\b' for backspace, '\f' for form feed, and '\t' for tab.
Variables are data that can change. They are declared with a data type like int followed by the variable name, and defined by assigning a value with the = operator. Variable names must start with a letter or underscore, can include letters, numbers and underscores, and cannot contain special characters or spaces. Variable names are case sensitive.
The document discusses the evolution of programming languages from machine languages to higher-level languages. It begins with an overview of the three main categories: machine languages, assembly languages, and higher-level languages. It then provides more details on each category, explaining that machine languages use binary, assembly languages use cryptic phrases, and higher-level languages use more English-like syntax. It specifically discusses third-generation languages as the first to use true English phrases.
Here are the key hardware components of a computer:
- Central processing unit (CPU) - The brain of the computer that processes data
- Memory - Temporarily stores data and instructions for processing
- Storage devices - Permanently store data like hard drives, CDs, DVDs
- Input devices - Allow data/instructions to enter like keyboards, mice, scanners
- Output devices - Allow information to be presented like monitors, printers
UNDERSTANDING COMPUTERS
7
The CPU, memory, and storage devices work together to process and store data. Input
devices allow data entry, and output devices display processed information. Software
provides the instructions that tell the hardware how to function and what tasks
A review of the growth of the Israel Genealogy Research Association Database Collection for the last 12 months. Our collection is now passed the 3 million mark and still growing. See which archives have contributed the most. See the different types of records we have, and which years have had records added. You can also see what we have for the future.
Strategies for Effective Upskilling is a presentation by Chinwendu Peace in a Your Skill Boost Masterclass organisation by the Excellence Foundation for South Sudan on 08th and 09th June 2024 from 1 PM to 3 PM on each day.
Leveraging Generative AI to Drive Nonprofit InnovationTechSoup
In this webinar, participants learned how to utilize Generative AI to streamline operations and elevate member engagement. Amazon Web Service experts provided a customer specific use cases and dived into low/no-code tools that are quick and easy to deploy through Amazon Web Service (AWS.)
Beyond Degrees - Empowering the Workforce in the Context of Skills-First.pptxEduSkills OECD
Iván Bornacelly, Policy Analyst at the OECD Centre for Skills, OECD, presents at the webinar 'Tackling job market gaps with a skills-first approach' on 12 June 2024
This presentation was provided by Steph Pollock of The American Psychological Association’s Journals Program, and Damita Snow, of The American Society of Civil Engineers (ASCE), for the initial session of NISO's 2024 Training Series "DEIA in the Scholarly Landscape." Session One: 'Setting Expectations: a DEIA Primer,' was held June 6, 2024.
This document provides an overview of wound healing, its functions, stages, mechanisms, factors affecting it, and complications.
A wound is a break in the integrity of the skin or tissues, which may be associated with disruption of the structure and function.
Healing is the body’s response to injury in an attempt to restore normal structure and functions.
Healing can occur in two ways: Regeneration and Repair
There are 4 phases of wound healing: hemostasis, inflammation, proliferation, and remodeling. This document also describes the mechanism of wound healing. Factors that affect healing include infection, uncontrolled diabetes, poor nutrition, age, anemia, the presence of foreign bodies, etc.
Complications of wound healing like infection, hyperpigmentation of scar, contractures, and keloid formation.
বাংলাদেশের অর্থনৈতিক সমীক্ষা ২০২৪ [Bangladesh Economic Review 2024 Bangla.pdf] কম্পিউটার , ট্যাব ও স্মার্ট ফোন ভার্সন সহ সম্পূর্ণ বাংলা ই-বুক বা pdf বই " সুচিপত্র ...বুকমার্ক মেনু 🔖 ও হাইপার লিংক মেনু 📝👆 যুক্ত ..
আমাদের সবার জন্য খুব খুব গুরুত্বপূর্ণ একটি বই ..বিসিএস, ব্যাংক, ইউনিভার্সিটি ভর্তি ও যে কোন প্রতিযোগিতা মূলক পরীক্ষার জন্য এর খুব ইম্পরট্যান্ট একটি বিষয় ...তাছাড়া বাংলাদেশের সাম্প্রতিক যে কোন ডাটা বা তথ্য এই বইতে পাবেন ...
তাই একজন নাগরিক হিসাবে এই তথ্য গুলো আপনার জানা প্রয়োজন ...।
বিসিএস ও ব্যাংক এর লিখিত পরীক্ষা ...+এছাড়া মাধ্যমিক ও উচ্চমাধ্যমিকের স্টুডেন্টদের জন্য অনেক কাজে আসবে ...
বাংলাদেশ অর্থনৈতিক সমীক্ষা (Economic Review) ২০২৪ UJS App.pdf
computer hardware and software
1. COMPUTER
BASIC CONCEPTS IN COMPUTER HARDWARE AND
SOFTWARE
COMPUTER
THE NEED FOR COMPUTER LITERACY
“Information is power and Computers are amplifiers of information”
When a pregnant woman collapsed into hepatic coma, a surgeon contacted a
medical library. He needed immediate
information on blood transfusions from the blood banks. Using a computer
terminal and a retrieval program, the librarian searched more than half a
million documents in just a few minutes. Necessary information was given to
the surgeon and the patient recovered fully.
Most information retrieval do not involve life-or-death decisions, but quicker
computer assisted retrieval saves time and aggravation for many people.
Information is a powerful commodity and is the driving force in our economy
today. Since, the amount of available information doubles after every two
years or so, managing it becomes vital. The computer in fact, helps us to
manage information.
Most of us, if not all of us are affected by the computer even if we are not
actually using it. In the years to come, understanding the computer and its
2. uses and being able to use it will become as necessary as being able to use a
pen.
Before understanding the various parts that constitute the computer and the
working of the computer, let us list some of the benefits, applications and
limitations of the computer.
Benefits of Computers
The three main benefits of using computers are :
3
Speed
3
Accuracy
3
Capacity to take large amount of work.
Computer work at a very high speed and are much faster than humans. The
human equivalent of an average computer would be morethan one million
mathematicians working 24 hours a day.
In addition to being fast, computers are very accurate. If the input and the
instructions are accurate the output will also be accurate.
Unlike humans, computers do not get bored or tired. The monotony of
repetitive work for long hours do not affect the computers.
Applications of Computers
Computers are used in various fields ranging from making cartoon films to
space research.
Some applications of computers are:
3
Railway reservation
3
Banking and Accounts
3
Weather Forecast
3
Space Research
3
Medical Diagnosis
3. 3
Chemical Analysis
Limitations of Computers
The Computer is one of the most powerful tools ever developed. Yet, we read
articles about instances, when a man received a telephone bill of Rs.10000,
when he did not even have a telephone. Such failures sound amusing, but
they happen because of human errors.
Computers have to be expressively told what to do. They cannot perform
anything that is not defined.
TYPES OF COMPUTERS
Computers are categorized on the basis of size, sot and performance.
Generally, the larger the system, the greater is its processing speed, storage
capacity, cost and ability to handle large number of devices. The various
types of computers are:
3
Microcomputer
3
Personal computers
3
Minicomputers
3
Mainframes
3
Super computers
Microcomputers
Systems on the lower end of the size of the size scale are
microcomputers. They may be tiny special purpose devices dedicated to
carrying out a single task such as one inside a camera.
Personal Computers
The most popular form of computer in use today is the Personal Computer
generally known as the PC. The PC can be used for various applications. It
can be defined as a single user oriented and general purpose microcomputer.
4. It can perform a diverse range of functions, from keeping track of household
accounts to keeping records of the stores of a large manufacturing company.
Lap Top Computer
Lately, the Palmtops and Laptops have become very popular with their power
and portability.
Mini Computers
Mini computers are small, general-purpose computers. They can vary in size
from a small desktop model to the size of a small filing cabinet. A typical
mini system is more expensive than a PC and surpasses of PC in storage
capacity and speed. While most PCs are oriented towards single users, mini
systems are designed to handle the needs of multiple users, i.e., more than
one person can work on a mini at the same time.
Mainframe Computers
A mainframe is another form of a computer system that is generally more
powerful than a typical mini. Mainframes themselves may vary widely in cost
and capability. They are used in large organizations for large scale jobs.
However, there is an overlap between the expensive minis and small
mainframe models in terms of cost and capability.
Super computers
At the end of the size and capability scale, are the super computers. These
systems are the largest, fastest and most expensive computers in the world.
These computers are owned by large organizations. They are used for
complex scientific applications.
Special purpose and general purpose computers
5. You have read about the applications and types of computers. Computers can
also be categorized general purpose computers and special purpose
computers, depending on their area of application.
Special purpose computers are designed to perform specific functions only.
Computers used in industrial process control, for example, in a washing
machine, a space craft, or a robot fall under this category.
General purpose computer on the other hand, are fast data manipulating
systems. They are designed to automatically accept and store input data,
process it, and output the information. Computers used in scientific
applications weather forecasting, research and business data-processing like
payroll fall under the general purpose category.
DATA AND INFORMATION
The word data is plural datum, which means fact or raw information.
Information is organized or processed data. For example, 88, 99, 34 are
numbers i.e., data. But they alone do not give any information as to what
they are. However, if they are written as
Subject
Marks
English
88
Mathematics
99
History
34
then they become meaningful and are referred to as information.
Working
Working principle of a computer
Just as a human being can be seen as a combination of body and mind, so can
a computer. The computer is a two part system consisting of a body that is
the hardware and a mind that is the software. A computer therefore, is a
collection of electronic parts (body) with a set of instructions controlling it
(mind).
Most activities can be described in terms of the Input-Process-Output (I-P-O)
cycle. This can be best illustrated by an example.
Let us assume that, you are asked to add 1346 and 2936
3
You first hear the two numbers.
3
Store the numbers in your memory.
6. 3
Your brain adds the two numbers.
3
Then, the result (4281) is stored in your memory.
3
You either speak out the result or write it down depending on
requirement.
The numbers are input, added and the result is output here, the inputs are
1346 and 2935. the output is 4281. Your ear is the input device, brain is the
processing unit, and mouth is the output device.
A computer system too, follows the I-P-O cycle. To understand the I-P-O cycle
of a computer, let us take the example of an airline reservation system.
A person who wishes to travel by air from Singapore to New York fills in a
reservation request slip. This slip contains relevant data, i.e., details of the
name, age, place of destination, etc., of the customer. These customer details
are the inputs. The process in this case, included examining the flight
number, the date of the journey, the class requested, and determining
whether seats are available as per the reservation details.
As a result of this process, the information that either the person gets the
reservation or is unable to get the reservation is output. The output may be
in the form of a ticket, if seats are available, or a message turning down the
request. Incase the customer is given reservation, his details are stored in a
storage device.
Now, let us see how each component of the PC system is related to the I-P-O
cycle. The data in the form of request slip is input via the keyboard. Hence,
the keyboard becomes the input device. The processing is performed by a
component of the system unit called the microprocessor.
The information regarding availability of seats is displayed on the display
unit; Hence, the VDU becomes the output device. If a ticket is to be issued, it
is printed on a printer which is also an output device.
Thus, each component of the PC system is involved in the I-P-O cycle. The
system unit does the processing. The other components -the VDU, the
printer, and the keyboard are necessary in the input or output part of the I-PO cycle and are hence termed as I/O devices. Now you can identify the
components of a PC as:
i.
The monitor or the visual display unit (VDU) for output
ii.
The keyboard for input
7. iii.
The system unit (CPU) for processing
iv.
The printer for output
HARDWARE AND SOFTWARE
Computer hardware includes all the electrical, mechanical, and the electronic
parts of a computer. Any part that we can see or touch is the hard ware.
Computer hardware includes
3
System Unit
3
Peripheral devices
3
Input devices i.e. keyboard, mouse etc.
3
Output devices i.e. Display Unit, printer etc.
3
Storage devices like hard disk, floppy disks etc.
Software:
The functioning of the computer is not dependent on hardware alone. So,
what else is required?
It requires a set of instructions that tells the computer what is to be done
with the input data. In computer terminology, this set of instructions is called
a program and one or more programs is termed as software.
Let us understand hardware and software with an example. An audio
cassette when played gives you some sound. Here, the tape recorder and the
audio cassette can be compared to hardware. The sound which comes from
the tape recorder can be compared to software.
Software used for computers may be of different types. Some of which are :
3
Application Software
3
System Software
8. You read about application of computer and identified certain areas where
computers are used today.
Applicatioin Software
Software specially suited for specific applications for example, railway and
airline reservation, billing, accounting or software which enables creation
and storage of documents are termed as application software.
System software In the above airline reservation example, the clerk types
your name and other details through the keyboard. But how does this go to
the system unit? This activity is done by a set of instructions called the
Operating Systems.
The Operating System manages the various 1/0 devices of the computer and
enables the user to interact with the machine.
The computer understands only machine language i.e. 0’s and 1’s. In the
above example how do you think it understands the reservation clerk’s query
in English? There has to be a software which translates the user language
into machine language.
The software which does this translation is known as the support software.
Examples of support software are compilers and interpreters.
For example, if you go to Italy and you do not know Italian, you would need
an interpreter to translate the English spoken by you into Italian.
COMPUTER COMPONENTS IN DETAIL
Keyboard :
A computer keyboard closely resembles a typewriter keyboard. It has
additional keys to handle special functions required by a computer.
A computer keyboard has three categories of keys:
3 Alphanumeric Keys (Alphabet & Numeric)
3 Special purpose keys
3 Function keys
9. ACTIVITY
1. Fill in the blanks.
a. .............................. is similar to the conductor of an orchestra
b. Computer programs are also known as
..............................................
c. A logical set of instructions to accomplish a job on a computer is called
a ................. ..................................................
d.
The equipment of a
..................................................
computer
system
is
called
................
Alphanumeric keys
Comprises of alphabets (A-Z), numbers (0-9) and other characters like
Special keys
They perform specific functions. Special keys are Enter (return), Backspace,
Insert, Delete, Home, End, Page Up (PgUp), Page Down (PgDn), Num Lock,
Caps Lock, Shift, Alt (Alternate), Ctrl (Control), Esc (Escape) and Cursor
(Arrow) keys.
Shift key when pressed with another key; alters the meaning of any
alphanumeric key for e.g. Shift with key 5 gives you ‘%’
The Ctrl and Alt keys when used with some other keys perform some special
functions e.g. Ctrl, Alt and Del pressed together restarts the system.
10. The Esc key is generally used to return to the previous menu or quit a
program. The Cursor is a symbol displayed on the screen at the position
where text or graphics will be inserted or deleted. The Cursor movement keys
move the cursor on the screen.
The Num Lock is used to activate the numeric keys on the Numeric keypad.
When Num Lock is off the keys work like cursor movement keys.
Scroll Lock is used to deactivate/activate scrolling of text on the screen.
Print Screen is used to print whatever is displayed on the screen.
Enter or Return is used to communicate the end of an instruction or data
being keyed in through the keyboard.
Caps lock is used for keying upper case alphabets.
Backspace is used to erase the character to the left of the cursor position.
The Function keys
These are used to perform a set of operations using a single keystroke. The
function keys can be defined as special purpose keys. In most of the software,
pressing the F1 key will take you to the help feature.
Other than these keys, 3 status indicator are present on the keyboard. They
are Caps Lock on/off, NumLock on/off, Scroll Lock on/off indicators.
Mouse
A mouse is an input devise which is used to points and select some options
on the VDU. A mouse may have one, two or three buttons. The function each
button depends on the program.
When a user rolls the mouse across a flat surface, such as a desk, the screen
cursor moves in the direction of the mouse’s movement. Clicking the mouse
results in selecting an option.
Positioning a cursor with the mouse is easier for non-typists than pressing
various key combinations. With an appropriate software, a mouse can also be
used to draw pictures.
Scanner
There are a number of situations when some information (picture or text) is
available on paper and is needed on the computer disk for further
manipulation. A scanner is used for this purpose A scanner scans an image
11. and transforms it into ASCII (special code used by the computers) and
graphics. These can be edited, manipulated and combined, and then printed.
Scanner are used to reproduce photographs on the computer screen. These
can be employed in training programs and in desktop publishing.
System Unit
The processing part of the I-P-O cycle takes place in the system unit. The
system unit consists of primary storage, arithmetic-logic unit, and the control
unit. The arithmetic-logic and control sections together make up the central
processing unit (CPU).
ArithmeticArithmetic-Logic Unit (ALU)
All calculation are performed in the arithmetic section, Operations like
comparing takes place in the logic section of the CPU
Control Unit
The control section of the CPU controls and directs the operation of the entire
system. It acts like the central nervous system for all the components though,
it does not process any data.
Primary Storage
Primary storage is used for four purposes.
3
To store the input data until the CPU is ready for processing.
3
As a working storage space like a sheet of paper used for
calculations.
3
As an output storage area that holds the finished results.
3
As a program storage area that stores the processing instructions.
These separate areas are not fixed. The size of each area varies from
application to application.
Primary storage consists of RAM, ROM, and cache
First of all you need to understand how the memory of a computer is
organized.
Bits and Bytes The computer can work with two states ON and OFF. ON
state is represented by 1 and OFF state is represented by 0. This system of
using 1’s and 0’s is called as the binary system.
12. A ‘0’ or a ‘1’ is called a bit. A collection of 8 bits is known as a byte. The
computer’s internal memory is organized as a collection of bytes. The size of
memory available is measured in Kilobytes (KB) or Megabytes (MB). One
Kilobyte represents 1024 bytes and one Megabyte represents 1024 Kilobytes.
The computer uses three types memory-the RAM, the ROM and cache.
RAM
Random Access Memory (RAM) is the area that is used for holding the
programs and their data while the computer is working with them. RAM
means the memory can be read from and written to randomly. The RAM is
also known as short term memory because once the power is switched off all
data in the RAM is erased.
ROM
It contains permanently recorded instructions that are vital for starting up a
computer. Instructions in ROM can be read but cannot be changed, hence the
name Read-Only Memory. Further, these instructions are not erased when
power goes off One set of instructions found in the ROM is called the ROMBIOS which stands for Read Only Memory Basic Input Output Services. This
set of programs perform the most basic control and supervisory operations for
the computer.
Cache Memory
A computer’s CPU is a fast device. But the storage devices are not as fast as
the CPU. Most of the time the CPU has to slow down because of these
devices. A small section of the high speed RAM is used to keep frequently
needed information.
Secondary storage
Computer’s primary storage or main memory is volatile and expensive. So,
one need some storage device to store data and other information. It should
be cheap and should not loose the content when power is switched off This
storage is called as the secondary storage. All secondary storage devices act
both as input and output devices. Magnetic storage media fulfills these
requirements and most common storage devices are disks and tapes.
13. Floppy Disk
It is the most common storage media and it helps transferring the data from
one computer to another. Floppies are classified based on their storage
density and data storage sides as
3
Single Sided Double Density (SSDD)
3
Single side High Density (SSHD)
3
Double Sided Double Density (DSDD)
3
Double Sided High Density (DSHD)
A diskette is divided into a series of concentric circles called tracks and
within that into sectors. Data is stored in these sectors. Each piece of data
that is stored, has a track number, a sector number and side number as an
address. So data can be accessed randomly from anywhere on the disk.
Hence, it is also called as Random Access storage.
Floppies come in two sizes - 5
floppy and 3
inch floppy.
Storage capacity of DSDD diskette is 360 KB. Storage capacity of a Double
Sided High Density diskette is 1.2 Mb.
Label Area you can write information like contents of floppy or the owner of
the floppy.
Write
Write Protect Area When this area is covered, the disk cannot be written to,
thus protecting your data. All important disks should be write-protected.
Index hole This is used by the floppy drive to determine the first sector of the
floppy.
Read/Write Area This area is used by the floppy drive to read and write data
to the diskette.
The 3 1/2
inch floppy
The 3 ½ inch double density floppy can store 720 KB and a high density
floppy can store 1.44 MB. The diskette is packed in a plastic case and has a
metal spring-loaded cover protecting the read/ write area.
The write protect tab is on the lower side of the floppy. When the hole is
closed you can write data onto the desk.
The label area is on the top side and the index hole is located at the metal
hub.
14. Hard Disk
The capacity of a hard disk is higher than that of a floppy. The most
significant difference between a floppy disk and a hard disk is that the hard
disk is completely sealed and is protected from dust and airborne particles.
The name hard disk comes from the rigid platter that is inside the drive. This
is , often called by different names like fixed disk or Winchester disk.
The hard disk comes in different shapes. Most hard disks nowadays store
something close to 500 MB. A hard disk has:
3
Platters to store data
3
Heads to read and write data from the platters.
3
A motor to rotate the platters
3
An electronic controller card that monitors the unit.
Data is stored in cylinders. Cylinders are nothing but, collection of tracks
located at the same distance from the outer edge of the each platter.
Magnetic tapes
Apart from using disks for external storage purposes, magnetic tapes are also
used for storing large amount data.
The magnetic tape could be a large reel or a small cassette. The tape is
essentially a plastic ribbon coated with some material that can be
magnetized. The data is recorded on these magnetic spots.
The data on the tape can however be read or written sequentially only.
Hence, it is called as sequential access storage.
Visual Display Unit (VDU)
This looks like a TV screen and is used to display information.
VDUs can work in two different modes viz. Text mode and graphic mode.
In text mode, the screen is divided into a matrix of rows and columns; each
cell of the matrix is used for one character. A typical screen has 80 character
positions per line and 25 lines across the screen.
15. In graphic mode, the screen is treated as an array of tiny dots called pixels.
The characters and pictures that appear on the screen are shown by making
a drawing of these pixels. The number of dots on the screen is called as
resolution. The higher the resolution the better the picture.
A typical high resolution monitor has 1024 x 768 pixels across the screen.
Further, a VDU can be a Colour VDU or a Monochrome depending on the
video mode. The formation of images on the screen is handled by the Video
Controller. The Video Controller along with the memory that holds the
display-data are together referred to as display adaptors. Some examples of
adaptors are Monochrome Graphics adaptor (MGA), Hercules Graphics
Adaptor (HGS), Super Video Graphics Array (SVGA).
ACTIVITY
1. Fill in the blanks.
a. ..............................are a mostly used for storing backup copies of data.
b. Magnetic disks are also called as ............................................
................................................
2. State true or false.
a.
Primary storage is used to store data permanently.
ACTIVITY
1.
State true or false
a.
A VDU needs memory to store the display data.
b.
VDU can also act as an input device.
Resolution is number of lines of VDU can display.
Printer
In order to get a copy of the output for later reference You would require a
printer. Printers are capable of printing at a very high speed. Two commonly
used printers are the dot-matrix printer and the laser printer. Printers are
classified on the basis of a number of parameters like, the mechanism used
for printing, speed of printing, quality of output, direction of printing, and the
kind of interface they have with the computer.
Printers can be broadly classified as impact and non-impact printers.
Let us understand this in detail.
16. Impact Printers
Impact printers work like typewriters.
The characters are printed by striking the paper i.e., characters are printed
by pressing a typeface against an inked ribbon a paper. Impact printers can
again be classified as Character printers and Line printers.
Character Printers
Character printers print one character at a time. Examples of character
printers are. Dot Matrix Printer and Daisy Wheel Printer.
Dot Matrix Printer
The most commonly used impact printer is the dot-matrix printer (DMP). In
a DMP, tiny hammers or pins strike the ribbon to produce the desired
characters. The print head consists of 9x7 array of pins. Characters to be
printed are sent one at a time to the printer. The characters printed are a
series of dots.
Dot-matrix are inexpensive but noisy. They can print both text and graphics.
They can print in any language without additional hardware change. They
can also be made to print in colour by changing ribbons. These printers are
used everywhere to produce internal reports and memos needed by
organizations.
Daisy Wheel Printer
In a daisy wheel printer, each petal has a character embossed on it.
A motor spins the wheel along with it. When the desired character spins to
the correct position, a print hammer strikes it to produce a character.
Line printers
Line printers print one line at a time. Hence, line printers are generally
faster than character printers. Printing speed varies from 150 lines to 2500
lines per minute. Some of the line printers are drum printers and chain
printers. These can continuously print for a few hours.
Drum printers
A drum printer consists of a cylindrical drum. The characters to be printed
are embossed on it.
A set of print hammers one for each character in a line, are mounted in front
of the drum A character is printed by striking the appropriate hammer
17. against the embossed character on the surface. The drum completes one
revolution to print one line.
The movement of the drum and the striking of the hammer must
synchronize. Otherwise, the printing will not be uniform. As printer drums
are costly they cannot be changed often.
Chain Printer
A chain printer has a steel band on which the characters are embossed. The
band is rotated at a high speed. As the band rotates, a hammer is activated
when the desired character comes in front of it. For every character there will
be a hammer. Here also, the hammer movement and the chain movement
must be synchronized. The main advantage of the chain printer is that its
chain can be easily changed. Thus, different fonts and scripts can be used
with the same printer.
NonNon-impact printers :
In non-impact printers, there is no contact between the typeface and the
paper while printing. Some examples of the non-impact are laser printer,
thermal printer, and inkjet printer.
Laser Printer
Laser printers print one page at a time. Laser printers use a light beam to
form images on the paper using a toner ink as the medium. Laser printers
are quiet workers. They produce very high quality output both text and
graphics. They are typically used publishing.
NonOther Non-impact printers
The other type of non-impact printers are thermal printers (which use heat to
print characters on paper) and inkjet printers (which use jets of ink to print
characters on paper). These printers are not in use as much as the laser
printers.
Printer Speed
The speed of a printer is measured in terms of cps (characters per second), lps
(lines per second) or ppm (pages per minute)
18. The speed of
3
a DMP is measured in cps
3
a Drum printer or a Chain printer in lps
3
a Laser printer in ppm
The speed of the printers can vary widely. For example, the speed of a MSP145 is 240 cps while that of MSP-155 is 300 cps. A line printer speed can be
anywhere from 5 to 50 lines per second. The speed of Xerox 4010 is 4 ppm.
LASER Jet IIISi 17 ppm and MT908 is 8 ppm.
Plotter
A plotter is used to create high-quality visuals on paper, which a printer is
incapable of doing. It can be used to create presentation-charts, graphics,
tables and high quality technical drawings.
There are two types of plotters : Drum and Flat Bed plotter.
Drum Plotter
The paper is placed over the drum that rotates back and forth. A carriage
holding one or more pens is mounted horizontally across the drum. The
carriage with the pens moves horizontally over the paper. Each pen could be
filled with different colours. This plotter has the ability to produce colour
pictures.
Flat Bed Plotter
In flat bed plotter, the paper does not move. The carriage holding the pens
should provide all motions. Inkjet plotters can also produce large drawings
with different colours.
SYSTEM UNIT IN DETAIL
Now that you are aware of the overall design of a computer system you can go
into little more detail about each component inside your system unit. Though
these details do not affect you as an end user, it completes your knowledge of
the computer.
19. System Unit
It is a box like structure of the computer. Inside this box you can find the
power supply, storage device, hard disk and floppy drives, and the mother
board containing CPU and memory.
It also contains expansion slots and cards to connect various input and
output devices. It can also contain optional cards like the modem card, mouse
card, video card, sound card. System unit or Main unit or Console comes in
two styles. Desktop model and Tower model.
Outside The Main Unit
Indicators
Power on indicator : it glows when the power is on.
Hard disk activity indicator : this gives the information as to whether the
hard disk is being accessed (read from or written to) or not.
Turbo mode indicator : This indicator is found in the PCs having dual speed
operation. It lets you know whether the system is running at a high or low
speed. When the indicator is ON, it shows that computer is working in high
speed mode (Turbo mode).
Power switch : Depending on the model of the computer, power switch can be
anywhere.
Reset switch : Pressing this switch restarts your computer, your power
supply.
Turbo switch : It is used for changing the speed of your computer to the
Turbo mode.
Key lock: Thus is meant for locking the keyboard. Once it is locked, the
computer does not accept any input from the keyboard.
Inside The System Unit
The Internal Power Supply
One of the main components inside the system unit is the power supply.
The Microprocessor
20. The CPU or the main microprocessor is the most important chip on the
motherboard. The entire design of the PC is based on this chip. The
computer’s performance depends directly on the CPU. The performance of
CPU depends on the model, version and speed.
Model
Each CPU has a specific model number assigned to it. Given below is the list
of common CPUs produced by Intel company in an increasing order of their
power, speed and performance.
80386, 80486, 80586 or Pentium.
Version
in each Model of CPU you may find further variations, such as SX, DX, DX2
etc. In this, SX is less powerful than DX and DX is less powerful than DX2.
Speed
The speed is measured in Megahertz. Higher the value, faster is the
information processed by CPU
Clock
All components should work in perfect synchronization, for the computer to
produce the desired results. The clock provides the timing signals in the form
of pulses that are used by the computer components to synchronize their
work. The clock chip uses a quartz crystal. The speed of the clock is measured
in MHz.
Speed of Operation
Speed of a computer can be assessed either in terms of the processing
capacity of the microprocessor or by the speed of the computer is measured in
MIPS (Million Instructions Per Second).
80386 Model can process 32 bits at a time, has a clock speed of 33 MHz and
has a speed of 0.4 MIPS.
The
The Memory
The internal memory of the PC is in the form of chips.
21. The Bus
Communication between the microprocessor, the memory chips, and another
chips found on the motherboard is accomplished a set of wires running
between them. This set of wires is called the bus.
The Ports
As in human terminology, ports are used to receive and send goods.
Similarly, the I/O devices like the keyboard, the printer etc. are connected to
the system unit through ports. These ports could be serial or parallel. a serial
port, is one where eight bits queued up and sent bit. In the parallel port all
the eight bits are transferred simultaneously.
The Storage System
The hard disk drive and floppy diskette drive are also mounted in the system
unit.
How Does A System Start?
StartThe Start-up Process
Every time a computer is switched on, it goes through a series before the user
is permitted to interact with it.
Stored in the ROM is a set of instructions that check each functional areas of
the computer. These instructions are called the power on self test (POST)
power
program. Forms a part of the ROM-BIOS. The POST checks the entire RAM
area and tests the connections to the various hardware devices attached, like
the keyboard, the disk drive, etc.
If problem occurs with any of the connections to the hardware devices or with
the RAM, POST program reports this on the screen.
The bootstrap process
Once the POST is over the next stage is called the ‘bootstrap’ process. Now
the computer waits for the operating system to take over. In the BIOS itself,
there is small program called the bootstep loader, which copies the Operating
System from the floppy or hard disk to the RAM. The bootstrap loader first
22. checks the A drive for a bootable disk. (A disk that has the Operating System
is a bootable disk). If the disk in that drive is not bootable, an errors reported
if the floppy is not there in the drive, the hard disk drive is checked. If the
hard disk also does not have the operating system then the computer reports
‘Boot disk failure’. This process of loading or copying the operating system is
called booting.
Soft boot and Hard boot
The Computer system can be restarted by pressing the keys <Ctrl>, <Alt>,
and <Del> simultaneously. This is known as a soft boot. Using the reset
switch or switching off and then switching on the computer is known as a
hard boot.
Know your Computer ..... And care for it
Connecting your Computer
You must first comprehend the two main steps needed to get your PC
working They are :
3
Connecting the sytem unit, monitor, printer to the power supply.
3
Connecting the various components, etc., the monitor (VDU). Keyboard,
Mouse, And printer to the system unit.
Before making connections, make sure that the power supply to the PC,
printer and monitor is off, Connecting your system while the power is on may
cause permanent damage to the computer and its peripherals.
KeyboardKeyboard-System Unit Connection
Plug the keyboard into the circular keyboard socket (also called a port or
interface in computer jargon) on the rear panel. The position of the keyboard
socket on your system may be different.
Before inserting the cable, make sure that the pin in the cable are lined up
with respect to the holes in the connector. Make sure the keyboard plug is
firmly fitted in the keyboard socket.
MonitorMonitor-System Unit Connection
23. Monitor has two cables. One is connected between the monitor and computer,
referred to as the video cable. The other cable is connected between monitor
and power socket called the power cable. The power outlet may be present on
the rear panel of the system unit, in which case the power plug must be
connected to this outlet. Otherwise, it should be connected to the main power
supply.
The video cable will go into the respective socket only Generally, in all the
PCs this socket is marked as ‘MON’.
MouseMouse-System Unit Connection
The rear panel of a system unit has both serial and parallel ports. The serial
ports are numbered as COM1, COM2, ... and parallel ports are numbered as
LPT1, LPT2, A mouse could be a serial port mouse or a parallel port mouse.
You will have to connect it accordingly.
Connecting a mouse to the machine is not enough. A dedicated program
called the driver which comes with the mouse has to be executed as per
installation procedures given in the accompanying manual.
PrinterPrinter-System Unit Connection
Printer unit has two cables. One connecting the printer to the computer and
another connecting it to the power supply.
Printers are of two types-serial and parallel. Your printer manual will tell
you what kind of printer you have. One end of the printer cable will be
connected to the appropriate port on the real panel. The other end of the
cable has to be connected to the printer. The connector is tapered .so that you
can only connect the cable one way.
Normally, you will find small wire clamps on either side of the port to hold
the connector securely. With the cable connected, press the wire clamps into
the notches.
Power Connection
It is better to connect the PCs to some constant power supply device. This is
required to avoid any damage that could be caused because of power
fluctuations. The commonly used protection devices are Voltage Stabilizers,
24. Constant Voltage Transformers (CVTs), and Uninterrupted Power Supplies
(UPSs).
In case, you have a CVT or an UPS, connect your computer’s power cable to
the CVT or UPS. The CVT’s power cable in turn is to be connected to the
mains.
Operating your Monitor
The ON/OFF switch is used to switch on/ switch off the monitor. A monitor
has a light indicator to show whether it is on or off.
The brightness and contrast control knobs are used to adjust the brightness
and sharpness of the text or image on the screen, respectively (similar to the
controls present on a TV).
Some monitor also have knobs to position the image at the centre of the
screen, these are the vertical shift and horizontal shift knobs used to shift the
image vertically and horizontally, respectively. When you are satisfied that
everything is working as it should, turn the power switch off to stop the test.
Maintaining your Computer
To keep your computer system working properly, it is necessary to protect the
hardware from environmental hazards, unreliable power supply and natural
calamities.
The following are some do’s and don’ts for a computer and its components.
General Precautions
Points to be borne in mind while using your PC:
Do
Keep your computer system in a cool, dry, and dust-free environment.
Ensure that the power switches on the system unit, monitor and printer
are OFF before switching on the mains.
Switch off the monitor, system unit and the printer, before switching off
the mains.
Clean the computer work area everyday; cover your system at the end of
the day.
25. Keep your system away from room walls to ensure proper air flow
around the computer.
Do Not
Allow eating or drinking near the computer.
Smoke in the vicinity of your computer.
Allow direct sunlight to fall on your computer.
Run any electric equipment like a vacuum cleaner in the vicinity of the
computer when it is on.
Maintaining your System Unit
Do
Park the hard disk before shifting the machine, when the unit needs to
be transferred from one site to another.
Parking refers to positioning the disk head on an unused area to ensure
that the head does not damage the disk.
Handle the floppy drive lever gently.
Ensure that there is no diskette in the floppy drive before switching off
the system unit.
Do Not
Switch on the system with a data floppy in the drive.
Insert or remove the diskette when the drive select indicator is glowing.
Switch off the system when the hard disk drive is active, i.e. when the
indicator is glowing.
Maintaining your Monitor
Do
Keep the brightness and contrast at minimum before switching on the
system, and increase it to the appropriate level thereafter.
Do Not
Try to open the VDU and touch the parts as these parts may carry high
voltage.
Maintaining Your Keyboard
Do
26. Clean the keyboard regularly.
Use a vacuum cleaner keyboards as it can extract the dust collected
between the keys.
Do Not
Strike the keys hard as those of a manual typewriter since these keys
are soft touch.
Rest your hands on the keyboard.
Keep anything on the keyboard.
Use the keys after switching off the system.
Stretch the keyboard cable.
Maintaining your Mouse
Do
Use a mouse pad.
If you do not have one, make sure you place the mouse on a clean
surface.
Cleaning a mouse
The ball and the rollers must be kept free of dust, dirt and grime. Most
mice can be opened and cleaned, clean them once in two months, or
when you notice that the pointer on the screen is not moving smoothly.
Following are the general steps to clean the mouse. Refer to the manual
to check for any variations.
Switch off the power supply and disconnect the mouse.
Remove the back cover (refer to the mouse manual to do this).
Remove the ball.
Clean the ball with lukewarm water and mild detergent; see that you do
not scratch its surface.
Dry the ball with a soft cloth.
Carefully clean the rollers using a toothpick, cotton wool or a soft cloth.
Replace the ball in its chamber.
Connect the cable and switch on the supply.
Do Not
Pull the mouse cable.
27. Expose the mouse to excessive moisture.
ACTIVITY
ACTIVITY
Create a file and feed sample data.
List out the various configuration of the computers and the move - discuss
the merits and demerits.
SUMMARY
#
Information is power and Computer help us in managing information.
Since this is the information age, computer literacy is needed.
#
Computers are used in various fields ranging from making carton films
to space research. They are used in Medicine, Research and Commercial
areas.
#
There main benefits of computers are speed, accuracy and ability to take
large amounts of work
#
Computers cannot do anything on their own. They have to be explicitly
told what is to be done.
#
Computers work on the principle of Input-Process-Output. A computer
takes the input, processes it, and produces the result.
#
A set of instructions is called a program. A collection of programs is
called Soft- ware. Software is of two types-System software and
Application software.
#
Keyboard, Mouse, Scanner are some of the Input devices.
#
Processing of I-P-O cycle takes place in System Unit. System Unit
consists of Arithmetic Logic Unit and Control Unit and Memory.
#
Primary Memory is comprised of RAM, ROM, cache. RAM is volatile.
ROM is non- volatile. ROM has a set of instructions to start the
computer. Cache is fast and small memory.
#
To store data and programs permanently secondary storage devices are
used.
Diskettes, Hard disks, Tapes are secondary storage devices.
28. #
To get a copy of the output on paper printers are used.
#
Plotters are used to produce high quality output.
#
System Unit consists of Motherboard, Power Supply, Speaker and Disk
drives. Outside the system units are various switches and indicators.
#
Before connecting any component of a computer ensure that the power is
off
# Loading the Operating System into the memory is called Booting.
#
Computers are used in various fields ranging from making carton films
to space research. They are used in Medicine, Research and Commercial
areas.
#
There main benefits of computers are speed, accuracy and ability to take
large amounts of work
#
Computers cannot do anything on their own. They have to be explicitly
told what is to be done.
#
Computers work on the principle of Input-Process-Output. A computer
takes the input, processes it, and produces the result.
#
A set of instructions is called a program. A collection of programs is
called Soft- ware. Software is of two types-System software and
Application software.
#
Keyboard, Mouse, Scanner are some of the Input devices.
#
Processing of I-P-O cycle takes place in System Unit. System Unit
consists of Arithmetic Logic Unit and Control Unit and Memory.
#
Primary Memory is comprised of RAM, ROM, cache. RAM is volatile.
ROM is non- volatile. ROM has a set of instructions to start the
computer. Cache is fast and small memory.
#
To store data and programs permanently secondary storage devices are
used.
Diskettes, Hard disks, Tapes are secondary storage devices.
#
To get a copy of the output on paper printers are used.
29. #
Plotters are used to produce high quality output.
#
System Unit consists of Motherboard, Power Supply, Speaker and Disk
drives. Outside the system units are various switches and indicators.
#
Before connecting any component of a computer ensure that the power is
off
# Loading the Operating System into the memory is called Booting.