This document discusses various computer input and output devices. It describes common input devices like keyboards, mice, scanners, microphones, and bar code readers. It also covers various types of output devices such as printers (impact, non-impact, inkjet, laser), monitors, plotters, and optical storage devices like CDs and DVDs. The document provides details on the purpose and functioning of many frequently used I/O devices.
The document discusses various input, output, and memory devices used in computers. It describes keyboards as the most common input device used to enter data and mice as input devices that control cursor movement. Monitors and printers are discussed as main output devices that display and print output. Memory devices covered include RAM and ROM as primary memory and their types. Secondary memory is also briefly mentioned.
The document introduces various input and output devices used in computing. It describes common input devices like keyboards, mice, scanners and touch screens that allow data to enter the computer. It also outlines output devices such as printers, monitors, and plotters that allow the computer to display and print information in human-readable form. The document provides details on the purpose and functioning of different types of both input and output devices.
Computer Fundamentals Input and Output devicesKirti Verma
Peripheral devices that allow communication between the computer and outside world are called input/output devices. Input devices supply data and programs to the computer and include keyboards, mice, scanners, microphones. Output devices allow the computer to communicate information to users and include printers, monitors, speakers. Common input devices described are keyboards, mice, scanners, microphones. Common output devices described are printers, monitors, and speakers.
This document discusses different types of terminals and computer graphics. It describes dumb terminals as having only keyboard input and monitor output with no processing capabilities. Intelligent terminals can perform limited processing by accepting user input, performing editing, and formatting output for display. Point-of-sale terminals are used for retail transactions using a bar code reader. The document also discusses different types of computer graphics for business, video, and CAD/CAM applications.
Input devices such as keyboards, mice, and graphics tablets allow users to enter data into a computer. Output devices like computer monitors, printers, and plotters display or print the output from a computer. Common output devices include monitors to display information on screen, printers to print hard copies, and plotters which can print large, high-quality drawings and designs using ink pens on paper.
This document discusses various computer input, output, and memory devices. It describes common input devices like keyboards, mice, scanners, and magnetic ink character recognition devices. It also covers output devices such as monitors in CRT, LCD, LED forms and printers as impact printers like dot matrix and line printers, and non-impact printers. Memory devices discussed include primary memory like RAM and secondary storage devices like hard disks.
These concentration cards were created so that as I am teaching students about computer input devices I can have them engage in visual learning (pictures) and play hand-on games like concentration, or let them compete against each other in teams as to getting 6 examples of computer input/output devices correct.
Welcome to the presentation of input & outputajaya024
The document discusses various computer input and output devices. It describes keyboards, mice, scanners and other common input devices. It also covers output devices like monitors, printers and speakers. The document provides details on the classification and types of different input and output devices used in computers.
The document discusses various input, output, and memory devices used in computers. It describes keyboards as the most common input device used to enter data and mice as input devices that control cursor movement. Monitors and printers are discussed as main output devices that display and print output. Memory devices covered include RAM and ROM as primary memory and their types. Secondary memory is also briefly mentioned.
The document introduces various input and output devices used in computing. It describes common input devices like keyboards, mice, scanners and touch screens that allow data to enter the computer. It also outlines output devices such as printers, monitors, and plotters that allow the computer to display and print information in human-readable form. The document provides details on the purpose and functioning of different types of both input and output devices.
Computer Fundamentals Input and Output devicesKirti Verma
Peripheral devices that allow communication between the computer and outside world are called input/output devices. Input devices supply data and programs to the computer and include keyboards, mice, scanners, microphones. Output devices allow the computer to communicate information to users and include printers, monitors, speakers. Common input devices described are keyboards, mice, scanners, microphones. Common output devices described are printers, monitors, and speakers.
This document discusses different types of terminals and computer graphics. It describes dumb terminals as having only keyboard input and monitor output with no processing capabilities. Intelligent terminals can perform limited processing by accepting user input, performing editing, and formatting output for display. Point-of-sale terminals are used for retail transactions using a bar code reader. The document also discusses different types of computer graphics for business, video, and CAD/CAM applications.
Input devices such as keyboards, mice, and graphics tablets allow users to enter data into a computer. Output devices like computer monitors, printers, and plotters display or print the output from a computer. Common output devices include monitors to display information on screen, printers to print hard copies, and plotters which can print large, high-quality drawings and designs using ink pens on paper.
This document discusses various computer input, output, and memory devices. It describes common input devices like keyboards, mice, scanners, and magnetic ink character recognition devices. It also covers output devices such as monitors in CRT, LCD, LED forms and printers as impact printers like dot matrix and line printers, and non-impact printers. Memory devices discussed include primary memory like RAM and secondary storage devices like hard disks.
These concentration cards were created so that as I am teaching students about computer input devices I can have them engage in visual learning (pictures) and play hand-on games like concentration, or let them compete against each other in teams as to getting 6 examples of computer input/output devices correct.
Welcome to the presentation of input & outputajaya024
The document discusses various computer input and output devices. It describes keyboards, mice, scanners and other common input devices. It also covers output devices like monitors, printers and speakers. The document provides details on the classification and types of different input and output devices used in computers.
The document discusses various input and output devices used in computing. Monitors display the graphical user interface and show running processes, while mice and keyboards allow users to input information through movement and keystrokes. Printers provide output and come in laser or inkjet varieties for different printing needs. Optical drives read and sometimes write data to discs, and hard disk drives store operating systems, applications, and data on internal storage. Other input devices include touchpads, trackballs, video digitizers, and joysticks, while outputs include speakers, graph plotters, and sound cards.
The document discusses various types of computer input and output devices. It describes keyboards, mice, scanners, joysticks, light pens, and other input devices used to communicate data and instructions to computers. Output devices discussed include monitors, printers, speakers, and projectors used to display or present the processed data to users. The key functions and characteristics of different input and output hardware are provided.
The document discusses input and output devices used with computers. It defines input devices as those used to provide data and control signals to computers, like keyboards, mice, microphones, and scanners. Output devices are used to display or present the results of processed data, such as monitors, printers, speakers, and projectors. The document provides examples of various types of input devices including keyboards, mice, microphones, digital cameras, and barcode readers. It also provides examples of output devices such as monitors, printers, speakers, headsets, and plotters. Some devices like CD drives and USB drives can act as both input and output devices by allowing data to be both input and accessed from storage.
The document discusses various input, output, and memory devices used in computers. It describes keyboards, mice, touch screens, microphones, and other input devices. Output devices mentioned include monitors, printers, plotters and speakers. The main types of computer memory are described as random access memory (RAM), read only memory (ROM), cache memory, and various secondary storage devices such as hard disks, floppy disks, CDs, DVDs, magnetic tapes, flash drives, and cloud storage.
The document discusses the basic components of a computer system: input, processing, output, and storage. It provides examples of common input devices like keyboards and mice, output devices like monitors and printers, and storage media like magnetic disks, optical disks, and solid-state drives. It also provides more details on specific types of these components in separate sections.
The document discusses various types of computer devices. It describes input devices like keyboards and mice that allow users to enter data. It explains output devices like monitors, printers and speakers that display or present data to users. It details processing devices like the CPU, GPU and motherboard that handle intermediate processing of data. It also outlines communication devices such as modems, routers and WiFi cards that enable data transfer and networking.
Input and output devices allow people to enter data into computers and receive processed results. Key input devices include keyboards, pointing devices like mice, scanners, and microphones. Output is delivered through permanent devices like printers and plotters that provide hard copies, and temporary devices like monitors and speech synthesizers that offer immediate visual and audio output. Some action output devices control machines and robotics.
The document discusses various input and output devices used in computer systems. It begins by defining input/output devices and their roles in facilitating communication between computers and the external world. It then describes several commonly used input devices such as keyboards, pointing devices, scanners, and microphones for speech recognition. The document provides examples and diagrams to illustrate how these devices function. It aims to help readers understand the basic concepts and purposes of the different I/O devices used in computer systems.
Input devices
WHAT IS INPUT?
WHAT ARE INPUT DEVICES?
WHAT IS HARDWARE?
WHAT IS SOFTWARE?
input Devices
1) KEYBOARD
2) POINTING DEVICES
3) MOUSE
TYPES OF MOUSE
1. Mechanical mouse
2. Optical mouse
3. Wireless mouse
JOY STICK
TRACKBALL
TOUCHPAD
TOUCHSCREEN
DIGITAL PEN
LIGHT PEN
WHEEL
BIOMETRIC INPUT DEVICES
VOICE RECOGNITION
THUMB IMPRESSION
SIGNATURE VERIFICATION
RETINA SCANNER
FACE RECOGNITION
MIC/ HEAD PHONE
DIGITAL CAMERA
DIGITAL SCANNER
The document discusses various input and output devices used in computer systems. It describes common input devices like the keyboard, mouse, scanner, microphone, and touchscreen. It also discusses output devices such as monitors, printers, and speakers. Input devices are used to enter data and instructions into the computer, while output devices are used to communicate the results of processing to users.
Input Output Device | Computer Fundamental and OrganiationSmit Luvani
It's all about how computer takes input or give output.
Covered Topics :
Bus > Serial Port, Parallel Port, USB Port
Input Units:
> Keyboard, MICR, OMR, OCR,
OUput Unit:
> Printer (Types of Printer and work operation), CRT
Automatic input devices can enter data into a computer without human involvement. This includes magnetic ink character recognition (MICR) readers that can read 300 cheques per minute with 100% accuracy, optical mark readers that can scan 10,000 forms per hour to collect data from multiple choice tests, and barcode readers that automatically scan products to identify them and retrieve price information from a database. Other automatic input devices discussed are magnetic stripe readers that extract data from credit cards, biometric fingerprint or retinal scanners, and sensors that can automatically detect quantities like temperature, light, and pressure.
Output devices receive information from the computer and translate it into a form that is readable by humans or other machines. There are two main types of output: hard copy, which provides a relatively permanent printed output, and soft copy, which is transient and disappears when the computer is turned off. Common output devices include printers, monitors, speakers, headphones, plotters, and projectors. Printers can be either impact printers, which use mechanical contact, or non-impact printers, which have no physical contact. Monitors include LCD, CRT, and digital displays. Speakers convert electrical signals to sound.
The document discusses input and output devices for computers. It provides examples of common input devices like keyboards, mice, scanners, and touch screens. It also provides examples of output devices like monitors, printers, and speakers. The document contains detailed descriptions and images of each device's purpose and function. It explains how input devices provide data to computers and output devices communicate data from computers to users.
Hardware devices that are used to input and output data to a computer are called I/O devices. Input devices capture information from the external environment and convert it into a format that can be processed by the computer. Examples include keyboards, mice, scanners, microphones, and webcams. Output devices take the processed data from the computer and present it to the user. Common output devices are monitors, printers, speakers and plotters. Monitors display soft copy output while printers provide hard copy printouts.
Computer – Hardware
Hardware represents the physical and tangible components of a computer, i.e. the components that can be seen and touched.
Examples of Hardware are the following −
Input devices − keyboard, mouse, etc.
Output devices − printer, monitor, etc.
Secondary storage devices − Hard disk, CD, DVD, etc.
Internal components − RAM,CPU, motherboard, etc.
INPUT AND OUTPUT DEVICES OF COMPUTER Input Devices A device that can be used to insert data into a computer system is called as input device. It allows people to supply information to computers without any input devices, a computer would only be a display device and not allow users to interact with it, Examples of input devices include keyboards, mouse, scanners, digital cameras and Light pen, joysticks, Touch-screen, OMR, OBR,OCR. Keyboard Most common and very popular input device is keyboard. The keyboard helps in inputting the data to the computer. The layout of the keyboard is like that of traditional typewriter, although there are some additional keys provided for performing some additional functions. Keyboard is of two sizes 84 keys or 101/102 keys, but now 104 keys or 108 keys keyboard is also available for Windows and Internet. Mouse Mouse is most popular Pointing device. It is a very famous cursor-control device. It is a small palm size box with a round ball at its base which senses the movement of mouse and sends corresponding signals to CPU on pressing the buttons. Generally it has two buttons called left and right button and scroll bar is present at the mid. Mouse can be used to control the position of cursor on screen, but it cannot be used to enter text into the computer.
Input and Output Devices PPT by Aamir Saleem AnsariTech
An input device sends information to a computer system for processing, and an output device reproduces or displays the results of that processing. Depending on the interaction, a device can be both, referred to as an input/output or I/O device.
For example, as you can see in the top half of the image, a keyboard sends electrical signals, which are received by the computer (input). Those signals are then interpreted by the computer and displayed on the monitor as text (output). In the lower half of the image, the computer sends data to a printer, which will print the data onto a piece of paper (output).
An input device can send data to another device, but it cannot receive data from another device. Examples of an input device include a computer keyboard and mouse, which can send data (input) to the computer, but they cannot receive or reproduce information (output) from the computer.
An output device can receive data from another device, but it cannot send data to another device. Examples of an output device include a computer monitor, projector, and speakers, which can receive data (output) from the computer, but they cannot send information (input) to the computer.
Input devices allow users to enter data and instructions into a computer and include mice, keyboards, scanners, joysticks, and bar code readers. Output devices display or present data from the computer to the user and include computer monitors, printers, plotters, microfilm, and speakers. Common printers include dot matrix, inkjet, and laser printers. Input devices convert user input into a form that computers can understand while output devices share the processed data back to users.
Input and output devices allow interaction between users and computers. Input devices receive data for processing while output devices display or print the processed data. Common input devices include keyboards, mice, scanners, microphones, and webcams. Keyboards allow text input while pointing devices like mice allow navigation. Scanners digitize physical documents and images. Microphones and webcams capture audio and video.
History of Multimedia Systems
- Newspapers were early adopters of multimedia, using text, graphics, and images. Radio and television further expanded multimedia capabilities for mass communication.
- Important developments included Bush's 1945 proposal of the Memex, the birth of the internet in the 1970s, and Tim Berners-Lee's 1989 proposal of the World Wide Web.
- Modern multimedia systems incorporate capture devices, storage, networks, computer systems, and high-quality display and output devices to process multiple media formats.
The document introduces input and output devices used in computing. It describes various input devices like keyboards, mice, scanners that allow data to enter a computer. It also covers output devices like printers, monitors, and plotters that allow a computer to display and print data in human-readable form. A variety of technologies are discussed for both inputting data into and outputting results from a computer system.
The document discusses various input and output devices used in computing. Monitors display the graphical user interface and show running processes, while mice and keyboards allow users to input information through movement and keystrokes. Printers provide output and come in laser or inkjet varieties for different printing needs. Optical drives read and sometimes write data to discs, and hard disk drives store operating systems, applications, and data on internal storage. Other input devices include touchpads, trackballs, video digitizers, and joysticks, while outputs include speakers, graph plotters, and sound cards.
The document discusses various types of computer input and output devices. It describes keyboards, mice, scanners, joysticks, light pens, and other input devices used to communicate data and instructions to computers. Output devices discussed include monitors, printers, speakers, and projectors used to display or present the processed data to users. The key functions and characteristics of different input and output hardware are provided.
The document discusses input and output devices used with computers. It defines input devices as those used to provide data and control signals to computers, like keyboards, mice, microphones, and scanners. Output devices are used to display or present the results of processed data, such as monitors, printers, speakers, and projectors. The document provides examples of various types of input devices including keyboards, mice, microphones, digital cameras, and barcode readers. It also provides examples of output devices such as monitors, printers, speakers, headsets, and plotters. Some devices like CD drives and USB drives can act as both input and output devices by allowing data to be both input and accessed from storage.
The document discusses various input, output, and memory devices used in computers. It describes keyboards, mice, touch screens, microphones, and other input devices. Output devices mentioned include monitors, printers, plotters and speakers. The main types of computer memory are described as random access memory (RAM), read only memory (ROM), cache memory, and various secondary storage devices such as hard disks, floppy disks, CDs, DVDs, magnetic tapes, flash drives, and cloud storage.
The document discusses the basic components of a computer system: input, processing, output, and storage. It provides examples of common input devices like keyboards and mice, output devices like monitors and printers, and storage media like magnetic disks, optical disks, and solid-state drives. It also provides more details on specific types of these components in separate sections.
The document discusses various types of computer devices. It describes input devices like keyboards and mice that allow users to enter data. It explains output devices like monitors, printers and speakers that display or present data to users. It details processing devices like the CPU, GPU and motherboard that handle intermediate processing of data. It also outlines communication devices such as modems, routers and WiFi cards that enable data transfer and networking.
Input and output devices allow people to enter data into computers and receive processed results. Key input devices include keyboards, pointing devices like mice, scanners, and microphones. Output is delivered through permanent devices like printers and plotters that provide hard copies, and temporary devices like monitors and speech synthesizers that offer immediate visual and audio output. Some action output devices control machines and robotics.
The document discusses various input and output devices used in computer systems. It begins by defining input/output devices and their roles in facilitating communication between computers and the external world. It then describes several commonly used input devices such as keyboards, pointing devices, scanners, and microphones for speech recognition. The document provides examples and diagrams to illustrate how these devices function. It aims to help readers understand the basic concepts and purposes of the different I/O devices used in computer systems.
Input devices
WHAT IS INPUT?
WHAT ARE INPUT DEVICES?
WHAT IS HARDWARE?
WHAT IS SOFTWARE?
input Devices
1) KEYBOARD
2) POINTING DEVICES
3) MOUSE
TYPES OF MOUSE
1. Mechanical mouse
2. Optical mouse
3. Wireless mouse
JOY STICK
TRACKBALL
TOUCHPAD
TOUCHSCREEN
DIGITAL PEN
LIGHT PEN
WHEEL
BIOMETRIC INPUT DEVICES
VOICE RECOGNITION
THUMB IMPRESSION
SIGNATURE VERIFICATION
RETINA SCANNER
FACE RECOGNITION
MIC/ HEAD PHONE
DIGITAL CAMERA
DIGITAL SCANNER
The document discusses various input and output devices used in computer systems. It describes common input devices like the keyboard, mouse, scanner, microphone, and touchscreen. It also discusses output devices such as monitors, printers, and speakers. Input devices are used to enter data and instructions into the computer, while output devices are used to communicate the results of processing to users.
Input Output Device | Computer Fundamental and OrganiationSmit Luvani
It's all about how computer takes input or give output.
Covered Topics :
Bus > Serial Port, Parallel Port, USB Port
Input Units:
> Keyboard, MICR, OMR, OCR,
OUput Unit:
> Printer (Types of Printer and work operation), CRT
Automatic input devices can enter data into a computer without human involvement. This includes magnetic ink character recognition (MICR) readers that can read 300 cheques per minute with 100% accuracy, optical mark readers that can scan 10,000 forms per hour to collect data from multiple choice tests, and barcode readers that automatically scan products to identify them and retrieve price information from a database. Other automatic input devices discussed are magnetic stripe readers that extract data from credit cards, biometric fingerprint or retinal scanners, and sensors that can automatically detect quantities like temperature, light, and pressure.
Output devices receive information from the computer and translate it into a form that is readable by humans or other machines. There are two main types of output: hard copy, which provides a relatively permanent printed output, and soft copy, which is transient and disappears when the computer is turned off. Common output devices include printers, monitors, speakers, headphones, plotters, and projectors. Printers can be either impact printers, which use mechanical contact, or non-impact printers, which have no physical contact. Monitors include LCD, CRT, and digital displays. Speakers convert electrical signals to sound.
The document discusses input and output devices for computers. It provides examples of common input devices like keyboards, mice, scanners, and touch screens. It also provides examples of output devices like monitors, printers, and speakers. The document contains detailed descriptions and images of each device's purpose and function. It explains how input devices provide data to computers and output devices communicate data from computers to users.
Hardware devices that are used to input and output data to a computer are called I/O devices. Input devices capture information from the external environment and convert it into a format that can be processed by the computer. Examples include keyboards, mice, scanners, microphones, and webcams. Output devices take the processed data from the computer and present it to the user. Common output devices are monitors, printers, speakers and plotters. Monitors display soft copy output while printers provide hard copy printouts.
Computer – Hardware
Hardware represents the physical and tangible components of a computer, i.e. the components that can be seen and touched.
Examples of Hardware are the following −
Input devices − keyboard, mouse, etc.
Output devices − printer, monitor, etc.
Secondary storage devices − Hard disk, CD, DVD, etc.
Internal components − RAM,CPU, motherboard, etc.
INPUT AND OUTPUT DEVICES OF COMPUTER Input Devices A device that can be used to insert data into a computer system is called as input device. It allows people to supply information to computers without any input devices, a computer would only be a display device and not allow users to interact with it, Examples of input devices include keyboards, mouse, scanners, digital cameras and Light pen, joysticks, Touch-screen, OMR, OBR,OCR. Keyboard Most common and very popular input device is keyboard. The keyboard helps in inputting the data to the computer. The layout of the keyboard is like that of traditional typewriter, although there are some additional keys provided for performing some additional functions. Keyboard is of two sizes 84 keys or 101/102 keys, but now 104 keys or 108 keys keyboard is also available for Windows and Internet. Mouse Mouse is most popular Pointing device. It is a very famous cursor-control device. It is a small palm size box with a round ball at its base which senses the movement of mouse and sends corresponding signals to CPU on pressing the buttons. Generally it has two buttons called left and right button and scroll bar is present at the mid. Mouse can be used to control the position of cursor on screen, but it cannot be used to enter text into the computer.
Input and Output Devices PPT by Aamir Saleem AnsariTech
An input device sends information to a computer system for processing, and an output device reproduces or displays the results of that processing. Depending on the interaction, a device can be both, referred to as an input/output or I/O device.
For example, as you can see in the top half of the image, a keyboard sends electrical signals, which are received by the computer (input). Those signals are then interpreted by the computer and displayed on the monitor as text (output). In the lower half of the image, the computer sends data to a printer, which will print the data onto a piece of paper (output).
An input device can send data to another device, but it cannot receive data from another device. Examples of an input device include a computer keyboard and mouse, which can send data (input) to the computer, but they cannot receive or reproduce information (output) from the computer.
An output device can receive data from another device, but it cannot send data to another device. Examples of an output device include a computer monitor, projector, and speakers, which can receive data (output) from the computer, but they cannot send information (input) to the computer.
Input devices allow users to enter data and instructions into a computer and include mice, keyboards, scanners, joysticks, and bar code readers. Output devices display or present data from the computer to the user and include computer monitors, printers, plotters, microfilm, and speakers. Common printers include dot matrix, inkjet, and laser printers. Input devices convert user input into a form that computers can understand while output devices share the processed data back to users.
Input and output devices allow interaction between users and computers. Input devices receive data for processing while output devices display or print the processed data. Common input devices include keyboards, mice, scanners, microphones, and webcams. Keyboards allow text input while pointing devices like mice allow navigation. Scanners digitize physical documents and images. Microphones and webcams capture audio and video.
History of Multimedia Systems
- Newspapers were early adopters of multimedia, using text, graphics, and images. Radio and television further expanded multimedia capabilities for mass communication.
- Important developments included Bush's 1945 proposal of the Memex, the birth of the internet in the 1970s, and Tim Berners-Lee's 1989 proposal of the World Wide Web.
- Modern multimedia systems incorporate capture devices, storage, networks, computer systems, and high-quality display and output devices to process multiple media formats.
The document introduces input and output devices used in computing. It describes various input devices like keyboards, mice, scanners that allow data to enter a computer. It also covers output devices like printers, monitors, and plotters that allow a computer to display and print data in human-readable form. A variety of technologies are discussed for both inputting data into and outputting results from a computer system.
This document discusses input and output devices. It describes several major input devices including the keyboard, mouse, joystick, optical mark reader, light pen, bar code reader, and magnetic ink character reader. It then discusses various output devices such as monitors, printers (including impact printers like dot matrix printers and non-impact printers like inkjet and laser printers), speakers, plotters, and multimedia projectors. The document provides details on the purpose and functioning of these common input and output hardware devices used with computers.
This document discusses input and output devices. It describes several major input devices including the keyboard, mouse, joystick, optical mark reader, light pen, bar code reader, and magnetic ink character reader. It then discusses various output devices such as monitors, printers (impact printers like dot matrix printers and non-impact printers like inkjet and laser printers), speakers, plotters, and multimedia projectors. The document provides details on the purpose and functioning of these common input and output hardware devices used with computers.
Input and output devices allow a computer to communicate with the outside world. Input devices, like keyboards, mice, and cameras bring information into the computer, while output devices, like monitors, printers, speakers, and plotters send information out of the computer. Some input devices require physical operation, like keyboards and mice, while others are automatic sensors, such as barcode readers. Common output devices include monitors to display information visually and printers to produce hard copies.
COMPUTER FUNCTIONAL UNITS INPUT,OUTPUT,MEMORY,ALU,CU
COMPUTER LANGUAGES
GENERATIONS OF COMPUTER
OPERATIING SYSTENMS -DOS,LINUX,WINDOWS
NUMBER CONVERTIONS
The document discusses various input and output devices used in computing. It describes 17 common input devices including the keyboard, mouse, joystick, touchpad, scanner, microphone, and digital camera. It then explains 15 output devices such as the monitor, printers (inkjet, laser, dot matrix), and plotters. For each device, it provides details on how they work, examples of their uses, and advantages/disadvantages.
This document discusses various input devices for computers including pens, touch screens, game controllers, optical scanning devices, audiovisual devices, and video input devices. It describes how pens and touch screens allow for selection and input on screens, how game controllers enhance the gaming experience, how scanning and image input convert physical documents and images into digital formats, and how audiovisual and video devices enable input of sound, speech, music, and video into computers.
This document discusses computer input, output, and storage devices. It describes common input devices like the keyboard and mouse, and other devices such as trackballs, graphics tablets, and microphones. Storage media include magnetic, optical, and solid-state devices for permanent data storage. Monitors and printers are examples of output devices, with monitors producing soft copy and printers producing hard copy. Input and output devices connect to computers physically or wirelessly.
The document discusses various computer input, output, and memory devices. It describes keyboards, mice, scanners, and monitors as common input and output devices. It also discusses different types of memory devices, including hard disk drives, solid state drives, RAM, and ROM. The document provides definitions and examples of how these various hardware components facilitate input, output, processing and storage of data in a computer system.
peripheral device, also known as peripheral, computer peripheral, input-output device, or input/output device, any of various devices (including sensors) used to enter information and instructions into a computer for storage or processing and to deliver the processed data to a human operator or, in some cases, a machine controlled by the computer. Such devices make up the peripheral equipment of modern digital computer systems.
Peripherals are commonly divided into three kinds: input devices, output devices, and storage devices (which partake of the characteristics of the first two). An input device converts incoming data and instructions into a pattern of electrical signals in binary code that are comprehensible to a digital computer. An output device reverses the process, translating the digitized signals into a form intelligible to the user. At one time punched-card and paper-tape readers were extensively used for inputting, but these have now been supplanted by more efficient devices.
This document discusses various input, output, and memory devices. It describes different types of keyboards, mice, joysticks, and optical mark recognition devices as examples of input devices. As output devices it examines monitors, printers including impact, non-impact, inkjet, laser, and thermal printers, as well as plotters and speakers. It also discusses hard disk drives, floppy disk drives, and portable storage devices as examples of secondary memory and how cache memory works.
Charles Babbage created the first computer called the Analytical Machine in the 19th century to automate tedious mathematical calculations. Computers store, process, and retrieve data using hardware and software. Common input devices include keyboards, mice, scanners, microphones, and touch screens. Output is displayed on monitors or printed using printers, plotters, and speakers which produce audio output.
The document discusses various types of computer peripheral output devices. It describes monitors, which display information on a screen for users to view. Printers are also discussed, including how they work and different printer technologies like inkjet and laser printers. The document mentions other output devices such as plotters, speakers, DVD/CD-ROM drives, and headsets.
This document discusses various types of computer input and output devices. It describes keyboards, mice, scanners, joysticks, light pens, optical mark readers, microphones, digital cameras, digital camcorders, bar code readers, and MIDI devices as common input devices used to enter data into a computer. It also outlines monitors, printers, speakers, plotters, and projectors as standard output devices that display processed computer data on screens or print it onto paper.
The document discusses various computer input and output devices. It describes punched cards, keyboards, mice, light pens, scanners, touch screens, barcode readers, and voice recognition systems as common input devices. It also briefly covers dot matrix printers, daisy wheel printers, line printers, drum printers, chain printers, inkjet printers, and laser printers as examples of output devices.
The document discusses various input and output devices used in computing. It describes keyboards, mice, scanners, microphones, and joysticks as common input devices that allow users to enter data. It also discusses output devices like monitors, printers, speakers and projectors that display or convey information to users in an understandable form. The document provides details on how each of these devices functions in digital systems.
This document provides information on various computer input and output devices. It discusses keyboards, mice, scanners, digital cameras, touch screens, magnetic ink character recognition, optical character recognition, light pens, microphones, monitors, printers, speakers, plotters, hard disks, magnetic tapes, floppy disks, and optical disks as common input and output devices and how they are used. The document is written by R.D. Sivakumar and provides details on his educational qualifications and contact information.
This document discusses input and output devices. It describes manual input devices like keyboards, mice, and touch screens. It also covers automatic input devices such as magnetic ink character recognition and barcode readers. For output devices it mentions monitors, printers like laser and inkjet printers, and speakers. The document provides details on the use and purpose of each type of input and output device.
How to Make a Field Mandatory in Odoo 17Celine George
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Input DevicesInput Devices
Input devices are used to feed data and
instructions to the computer systems.
They consist of a range of devices that take
data and programs from the outside world that
people can read or comprehend and convert
them to a form that the computer can
manipulate.
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Input DevicesInput Devices
The form of the input devices :
Keyboard, Pointing device
Writing & drawing input devices
Video, Text, voice input
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Key board
It’s similar as normal typewriter
keyboard, plus a number of special keys.
Standard keys are used to enter words &
numbers. Special keys so called “function
keys” labeled as F1,F2 ... are used to
enter commands.
A numeric keypad that resembles an
electronic calculator’s keypad.
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Key board
Cursor-movement key
104-key enhanced keyboard
Used for data entry and to issue commands
into the system.
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Pointing device - Mouse
A mouse is a device that can be rolled on a
desktop to direct a pointer (cursor) on the
computers display screen. The cursor is the
symbol on the screen that shows where data
may be entered next or the command to be
activated.
Pointing devices commonly have two or three
buttons that are used to issue commands to the
computer.
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Pointing device - Mouse
Command Actions
Point - an act of moving the pointing
device to an object on-screen.
Click - select the object on-screen.
Drag - holding down the pointing-device
button while moving the selected object on-
screen.
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Pointing device - Trackball
A trackball performs like a stationary, upside-
down mouse.
Most portable laptop computers use a built-in
or clip-on trackball.
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Pointing device - Joystick
A joystick is a small lever that
can be moved in any direction
to move an object on the screen.
Usually associated with playing
computer games.
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Graphics Input - Scanner
Image scanners or graphic
scanners convert the printed or
photographic image on paper into
electronic signals and then into
digital form.
These digital information then can
be stored in a computer &
manipulated.
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Text Input - Scanner
Text are scanned from the printed page
into the computer, as an attempt to reduce
errors in data entry while speeding up the
process as well.
The software incorporated converts the
scanned images into character codes and
thus enables text processing.
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Text Input - OCR
Optical Character Recognition (OCR)
An input device that can read and recognise
the symbols of text (special printed characters)
& convert them to the machine readable form.
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Writing & Drawing Input
Devices - Light Pen
The light pen is a light sensitive stylus, or pen
like device, connected by a wire to the
computer terminal.
The user brings the pen to a desired point on
the display screen and presses the pen button,
which identifies that screen location to the
computer.
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Writing & Drawing Input
Devices - Touch Screen
The touch screen is
video display screen
that has been sensitized
to receive input from the
touch of a finger.
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Writing & Drawing Input
Devices - Digitizing Tablet
A digitizing tablet consists of a tablet
connected by a wire to a stylus or puck.
A stylus is a pen like device with which the
user “sketches” an image.
A puck is a copying device with which the
user copies an image as it is moved over a
desired path on a sketch.
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Writing & Drawing Input
Devices - Digitizing Tablet
More sophisticated
stylus or pointing
devices with high
accuracy are used by
designers, architects,
artists, desktop
publishers, map makers,
etc.
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Video input
(Digital Camera)
As with sound, most films & video are
generated and recorded in analog forms in
which the signals are in continuously varying
nature. Thus the signals come from the systems
such as VCR, videodisk or laser disk, or a
camcorder must be converted to digital form
through a special video capture card installed
in the computer.
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Video input
Two type of video cards:
Frame grabber video card
• Can capture & digitize only a single frame at a
time.
Full motion video card
• Can convert analog to digital signals at the rate
of 30 frames per second, giving the effect of a
continuously following motion picture.
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Voice input
(Voice Recognition)
Converts the person’s
speech in to digital code
by comparing the
electrical patterns
produce by the
speaker’s voice with a
set of prerecorded
patterns stored in the
computer.
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Source Data Input - MICR
Magnetic Ink Character Recognition (MICR)
MICR characters which are printed with magnetic
ink , containing magnetic particles are read by
MICR equipment producing digitised signals.
Used by banks to read the information such as
printed serial numbers on the bottom of cheques
using magnetic ink.
MICR reader/sorter can process cheques and other
documents at speeds of up to 2000 documents per
minute.
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Source Data Input – Magnetic strip
Used on the backs of credit cards and bank
debit cards, and various other plastic cards.
Enables readers, such as automated teller
machines (ATM) to read account information.
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Source Data Input - OMR
Optical-Mark Recognition (OMR)
An input device that senses marks on a piece
of paper, using a light beam, and converts
them into electronic signals which are sent to
the computer for processing.
Commonly used to mark the questionnaires or
school examination answer sheets where the
students, using pencils mark certain boxes on
the examination answer sheets provided.
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Source Data Input - Bar codes
Commonly used by
sales and stock people
in retail stores and
supermarkets.
Point-of-sale (POS)
terminal scans the bar
codes of the Universal
Product Code (UPC) to
register the price, which
is programmed into the
host computer, as well
as to deduct the item
from stock.
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Output devicesOutput devices
Translate information processed by the
computer into a form that human or another
machine can recognize.
The two principle kind of outputs are
hardcopy & softcopy .
Hardcopy refers to a printed output.
Softcopy refers to the information that is
shown on the display screen or is in
audio or video form.
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Output devicesOutput devices
There are several ways
to produce output:
Text output
Graphics output
Sound output
Video output
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Output devicesOutput devices
Text Output :
Simply the alphanumeric characters that
make up our language. Text output
appearance ranges from typewritten to
typeset quality.
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Output devicesOutput devices
Graphics Output :
Includes line drawings, maps, presentations
business graphics, computer-aided design,
computer painting, photographic
reproduction.
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Output devicesOutput devices
Sound output :
Ranges from the message beeps produced
by the computer system to the human voice
to music and other forms of sound.
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Output devicesOutput devices
Video output :
Photographs (still images) or moving
images such as television and videotaped
material.
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PrintersPrinters
A printer provides hard copy output on paper.
The basic criteria for evaluating printers
include:
QualityQuality of the printed output.
SpeedSpeed at which printed pages are produced.
SoundSound levellevel during printing.
CostCost of printing media (ribbons, cartridges).
ConservationConservation of paper.
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Translates information that has been processed byTranslates information that has been processed by
the system unitthe system unit
OutputOutput referred to as hard copyreferred to as hard copy
FeaturesFeatures
• ResolutionResolution
• Color capabilityColor capability
• SpeedSpeed
• MemoryMemory
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PrintersPrinters
Impact Printers :
Form characters or images by striking a
mechanism such as print hammer or wheel against
an inked ribbon leaving an image on paper. Make
high noise. Now used less.
Non- Impact Printers :
Form characters or images without making direct
physical contact between printing mechanism and
paper.
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Impact PrintersImpact Printers
First printing technology.
E.g. 24 Pin Okidata Dot Matrix Printers - 475 cps
Early days typewriters were adapted, produced same
high-quality output.
Cannot change fonts nor can print graphics or
colours. Only the symbols available in the printing
mechanism can be produced on the paper.
e.g. daisy wheel printer, drum and belt printers.
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Impact PrintersImpact Printers
Followed by dot-matrix printers.
Dot-matrix output is produced by printers that
use wires in the print head. These wires extend
out in different patterns, pressing against the
ribbon to print the characters on paper. As this
mechanism enables the print control up to the
dot level on the paper, the can be used to
produce both text and graphics.
Fast, but noisy. Wear out ribbons very quickly.
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Non-Impact Printers –Non-Impact Printers –
Laser PrintingLaser Printing
Provide high-quality non-impact printing. Output is
created by directing a laser beam onto a drum to
create an electrical charge that forms a pattern of
letters or images.
As the drum rotates, it picks up black toner on the
images and transfers them to paper. The heating
process then fixes the toner particles permanently
on the paper.
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Non-Impact Printers –Non-Impact Printers –
Laser PrintingLaser Printing
Excellent print quality and font selection.
Fast printing.
E.g. 8-500 pages per minute
High quality graphics with colour. High resolution.
Medium level noise, but high cost.
Primary disadvantages are expensive maintenance
and the high cost of toner cartridges.
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Non-Impact Printers –Non-Impact Printers –
Inkjet PrintingInkjet Printing
Inkjet printer transfers characters and images
to paper by spraying a fine jet of ink.
Offers nearly the quality of laser printing, but
not the speed. Low-cost alternative for high
quality printing.
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PlottersPlotters
It is a specialized output device designed to produce
high-quality graphics in a variety of colours. That are
especially useful for creating maps and architectural
drawings, although they may also produce less
complicated charts and graphics.
Type of plotters :
Pen plotter
Electrostatic plotter
Thermal plotter
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MonitorsMonitors
Known as screens orKnown as screens or
display screensdisplay screens
Output referred to asOutput referred to as
soft copysoft copy
FeaturesFeatures
• Resolution-pixelsResolution-pixels
• Dot pitchDot pitch
• Refresh rateRefresh rate
• SizeSize
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Cathode-ray tubeCathode-ray tube oror
CRTsCRTs
Flat-panelFlat-panel
• Require less power toRequire less power to
operateoperate
• Portable and thinner thanPortable and thinner than
CRTsCRTs
Other monitorsOther monitors
• E-booksE-books
• Data projectorsData projectors
• High-definition televisionHigh-definition television
(HDTV)(HDTV)
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Video MonitorVideo Monitor
Provides soft copy output.
Comes in either monochrome
or colour.
A monochrome display a single colour
against a different coloured background,
such as green on black amber on black
or white on black.
Colour display can show a variety of
colours.
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Video DisplaysVideo Displays
Resolution - describes the degree of
details in a video display.
The higher the resolution the characters
and images are sharper and crisper as
film image.
Conventional television display is low
resolution as we can see lines, jagged
edges and graininess in the image.
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Video DisplaysVideo Displays
Bit-mapped display offers extremely
high-resolution. Bit map means that each
dot on the screen, called a pixel (for
picture element) is represented by one bit
(a 1 or 0) by the computer. (monochrome)
Bit-mapped graphics is the colour version
of a bit map display. Each pixel identifies
a number (e.g. 1-256 on a 256-colour
palette) indicating what colour that pixel
should be.
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Video DisplaysVideo Displays
The liquid crystal display (LCD) is a
flat-screen display commonly used with
portable computers.
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TerminalTerminal
A monitor-keyboard combination.
Has no system unit of its own, but instead uses
the facility from a central computer via a
communication link.
Mainframes, minicomputers and workstation
systems support multiple terminals.
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TerminalTerminal
Dumb terminal performs the simplest input
and output operations but no processing.
e.g. A bank ATM
Smart (intelligent) terminal may have its
own CPU or processing capabilities, as well as
built-in disk for storage.
e.g. Point-of-sale (POS) cash register
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Optical Storage DevicesOptical Storage Devices
Data recording is done by using laser technology.Data recording is done by using laser technology.
Types of Optical Storage Devices :Types of Optical Storage Devices :
Compact Disk Read Only Memory (CD-ROM)Compact Disk Read Only Memory (CD-ROM)
Compact Disk Recordable drives (CD-R)Compact Disk Recordable drives (CD-R)
CD-ROM PlayersCD-ROM Players
CD-ROM TowersCD-ROM Towers
Erasable Optical Disk (EOD)Erasable Optical Disk (EOD)
CD-ROM JukeboxesCD-ROM Jukeboxes
DVD-ROM DrivesDVD-ROM Drives
Magneto-optical DrivesMagneto-optical Drives
Optical storage mediaOptical storage media
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CD-ROMCD-ROM
Holds approximately 650 MBHolds approximately 650 MB
Used for :Used for :
Data StorageData Storage
EncyclopaediasEncyclopaedias
CataloguesCatalogues
GamesGames
EntertainmentEntertainment
MoviesMovies
Magazines and booksMagazines and books
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DVD DevicesDVD Devices
OriginallyOriginally- Digital Video Disk (DVD)- Digital Video Disk (DVD)
NowNow - Digital Versatile Disk (DVD)- Digital Versatile Disk (DVD)
Refers to a storage medium that can store TV-qualityRefers to a storage medium that can store TV-quality
images on a CD-ROM disk with a capacity exceedingimages on a CD-ROM disk with a capacity exceeding
5 GB.5 GB.
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Removable media drivesRemovable media drives
Including tape drives, zip, LS120, and DAT drivesIncluding tape drives, zip, LS120, and DAT drives
except floppy drives.except floppy drives.
Magnetic TapesMagnetic Tapes
Very popular with mainframe computers.Very popular with mainframe computers.
Storage density is expressed in ‘bytes per inch’Storage density is expressed in ‘bytes per inch’
((bpibpi) or character per inch () or character per inch (cpicpi).).
Storage density varies with the quality of theStorage density varies with the quality of the
tape & the equipment used to read form andtape & the equipment used to read form and
write on it.write on it.
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Magnetic TapesMagnetic Tapes
Tape width = ½ inchTape width = ½ inch
Data storage in tracksData storage in tracks
Tape tracks = 9Tape tracks = 9
Data recorded in blocks of charactersData recorded in blocks of characters
Read/write speed = 50 ips (inches per second)Read/write speed = 50 ips (inches per second)
Recording density = 1,600 bpi (bytes per inch)Recording density = 1,600 bpi (bytes per inch)
Tape length = 2400 feet = 28,800 inchesTape length = 2400 feet = 28,800 inches
Storage capacityStorage capacity 40 MB40 MB
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Magnetic TapesMagnetic Tapes
Time to write a block = 128 msTime to write a block = 128 ms
Tape start/stop time = 0.02 sec = 20 msTape start/stop time = 0.02 sec = 20 ms
Time to write a block + start and stop timesTime to write a block + start and stop times
= 20 + 128 + 20 = 168 ms= 20 + 128 + 20 = 168 ms
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Digital TapeDigital Tape
Magnetic tapeMagnetic tape
A tape made of thin plastic with a magneticallyA tape made of thin plastic with a magnetically
layer on which data can be stored.layer on which data can be stored.
Digital tape store data in digital format, instead ofDigital tape store data in digital format, instead of
analogue format.analogue format.
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ZIP DevicesZIP Devices
Zip drive (portable or internal) uses a special 3.5 inchZip drive (portable or internal) uses a special 3.5 inch
disk that holds 100 Mb or 250 MB.disk that holds 100 Mb or 250 MB.
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Hard Disk Drive (HDD)Hard Disk Drive (HDD)
The mechanism that reads and writes data on a hardThe mechanism that reads and writes data on a hard
disk.disk.
A sealed unit that a PC uses for nonvolatile dataA sealed unit that a PC uses for nonvolatile data
storage.storage.
HDDs are sometimes calledHDDs are sometimes called Winchester drives.Winchester drives.
Used to store crucial programming and data.Used to store crucial programming and data.
Contains rigid, disk-shaped platters, usuallyContains rigid, disk-shaped platters, usually
constructed of aluminum or glass.constructed of aluminum or glass.
Many disk drives improve their performance through aMany disk drives improve their performance through a
technique calledtechnique called cachingcaching..
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Hard Disk Drive OperationHard Disk Drive Operation
HDD consists of spinning disks with headsHDD consists of spinning disks with heads
that move over the disk and store data inthat move over the disk and store data in
tracks and sectors.tracks and sectors.
The heads read and write data in concentricThe heads read and write data in concentric
rings called tracks.rings called tracks.
Tracks are divided into segments calledTracks are divided into segments called
sectors which store 512 bytes.sectors which store 512 bytes.
Disk consists of several platters (e.g. 3).Disk consists of several platters (e.g. 3).
Each platter has two sides. A number refersEach platter has two sides. A number refers
to each side (e.g. side 0, 1, 2, 3 for 4to each side (e.g. side 0, 1, 2, 3 for 4
surfaces). A Disc pack may have 20 surfacessurfaces). A Disc pack may have 20 surfaces
or = 11 Plattersor = 11 Platters
The platters can’t bend or flex.The platters can’t bend or flex.
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Magnetic Disk (Hard Disk)Magnetic Disk (Hard Disk)
Removable Disk :Removable Disk :
Removable disk pack used in earlier Mainframe &Removable disk pack used in earlier Mainframe &
Mini Computers.Mini Computers.
Disk cartridge - easy to remove like cassettes.Disk cartridge - easy to remove like cassettes.
Fixed Disk :Fixed Disk :
Installed in a sealed container and it’s notInstalled in a sealed container and it’s not
removable.removable.
most of the fixed disks use the “Winchester”most of the fixed disks use the “Winchester”
technology.technology.
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Magnetic DiskMagnetic Disk
A disk starts out very unstructured – just a lot of bitsA disk starts out very unstructured – just a lot of bits
of magnetic stuff without any organisation, rhyme orof magnetic stuff without any organisation, rhyme or
reason. Before the system can start writing records toreason. Before the system can start writing records to
it, the disk must have a structure a grid work intoit, the disk must have a structure a grid work into
which the information can be placed.which the information can be placed.
Formatting a disk is the process of putting the gridFormatting a disk is the process of putting the grid
work on the disk and building the organisationalwork on the disk and building the organisational
structure so that file can be found. Once a disk isstructure so that file can be found. Once a disk is
formatted it is ready for the system to write data to it.formatted it is ready for the system to write data to it.
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Magnetic DiskMagnetic Disk
Formatting organises disks into numbered ringsFormatting organises disks into numbered rings
called cylinders. A cylinder on a single side iscalled cylinders. A cylinder on a single side is
referred to as a track.referred to as a track.
Each track is broken into numbered pie slices calledEach track is broken into numbered pie slices called
sectors. Each sector stores information.sectors. Each sector stores information.
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Magnetic DiskMagnetic Disk
For an example,For an example,
Disk packDisk pack = 20 surfaces = 11 Platters= 20 surfaces = 11 Platters
Disk = 2048 cylinders (figure has only 4)Disk = 2048 cylinders (figure has only 4)
Cylinder = 20 tracks (track in each surface)Cylinder = 20 tracks (track in each surface)
Track = 72 sectors (figure outermost has 13)Track = 72 sectors (figure outermost has 13)
Sector = 512 bytesSector = 512 bytes
Disk Storage = 512 * 72 * 20 * 2048 bytes = 1.44 GBDisk Storage = 512 * 72 * 20 * 2048 bytes = 1.44 GB
Rotational speed = 3600 rpm (revolutions per minute)Rotational speed = 3600 rpm (revolutions per minute)
= 16.66 ms per revolution= 16.66 ms per revolution
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Magnetic DiskMagnetic Disk
The time required to position the read-write heads over theThe time required to position the read-write heads over the
required track is the seek time.required track is the seek time.
The time required for the read-write head to come to aThe time required for the read-write head to come to a
complete stop after it is moved is called the settling time.complete stop after it is moved is called the settling time.
The time required for the disk to rotate to the position whereThe time required for the disk to rotate to the position where
the beginning of the desired block arrives at the read-writethe beginning of the desired block arrives at the read-write
head is latency.head is latency.
Average Rotational delay (latency) = ½ revolutionAverage Rotational delay (latency) = ½ revolution
Track capacity = 72 x 512 = 36 KBTrack capacity = 72 x 512 = 36 KB
Cylinder capacity = 20 x 36 = 720 KBCylinder capacity = 20 x 36 = 720 KB
Disk capacity = 2048 x 720 = 1.44 GBDisk capacity = 2048 x 720 = 1.44 GB
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Hard Disk Technology –Hard Disk Technology –
RAID SystemsRAID Systems
Stands for Redundant Array of Independent (orStands for Redundant Array of Independent (or
Inexpensive) Disk.Inexpensive) Disk.
Designed to improve the fault tolerance andDesigned to improve the fault tolerance and
performance of computer storage systems.performance of computer storage systems.
The main purpose is to increase the reliability andThe main purpose is to increase the reliability and
availability.availability.
i.e. If one disk fails, still no data is lost.i.e. If one disk fails, still no data is lost.
RAID is an assembly of disk drives, known as diskRAID is an assembly of disk drives, known as disk
array, that operates as one storage unit.array, that operates as one storage unit.
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RAID SystemsRAID Systems
RAID functions are:RAID functions are:
Immediate availability of data and, dependingImmediate availability of data and, depending
on the RAID level, recovery of lost data.on the RAID level, recovery of lost data.
Redundancy of data at a chosen level.Redundancy of data at a chosen level.
Depending on the level of RAID, this method of dataDepending on the level of RAID, this method of data
storage provides the data redundancy needed for astorage provides the data redundancy needed for a
highly secure system, with additional benefit of fasterhighly secure system, with additional benefit of faster
retrieval of data through multiple channel access.retrieval of data through multiple channel access.
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RAID SystemsRAID Systems
The array includes drives, controllers, enclosure,The array includes drives, controllers, enclosure,
power supplies, fans, cables, etc. and software.power supplies, fans, cables, etc. and software.
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ModemsModems
A device used to provide remote connectivity over the
Telephone lines.
For two modems to communicate, must share the same
protocol.
Protocol :Protocol :
Determines how two entities will communicate.Determines how two entities will communicate.
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ModemsModems
Connection of informationConnection of information
superhighway is by way of a modem.superhighway is by way of a modem.
This is connected to the serial port ofThis is connected to the serial port of
the computer.the computer.
The faster modem, the less the time itThe faster modem, the less the time it
will take to download files to thewill take to download files to the
computer. If long distance telephonecomputer. If long distance telephone
charges are involved higher speedcharges are involved higher speed
modems can save cost as well time.modems can save cost as well time.
Modems with speeds as high as 56,000Modems with speeds as high as 56,000
baud are advisable.baud are advisable.
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ModemsModems
It converts digital data used by the computers intoIt converts digital data used by the computers into
analog signals for transmission over the telephoneanalog signals for transmission over the telephone
line & converts the analog signals back to digitalline & converts the analog signals back to digital
data. (Modulator & Demodulator)data. (Modulator & Demodulator)
Three modulation methods are:Three modulation methods are:
Frequency-shift keying (FSK)Frequency-shift keying (FSK)
Phase-shift keying (PSK)Phase-shift keying (PSK)
Quadrature amplitude modulation (QAM)Quadrature amplitude modulation (QAM)