INFORMATION TECHNOLOGY Presented By Manshi Makati Taught By , Asha Madam
INTRODUCTION TO INFORMATION TECHNOLOGY Information Technology is the application of Computers towards organizing and efficient retrieval/reporting of information. Information Technology refers to the creation, gathering, processing, storing, protecting, presenting and dissemination of information using , hardware, software and telecommunication technology.
WHAT IS INFORMATION TECHNOLOGY (IT) ANYWAYS ? As defined by “INFORMATION TECHNOLOGY ASSOCIATION OF AMERICA (ITAA)” “IT includes various types of Computers, Software, Communications, Facsimile transmissions, & Electronic conferencing.” By Henry C. Lucas, Jr “IT is the study, design, development, implementation, support or management of computer based information system particularly softwares applications & computer hardware.”
INFORMATION TECHNOLOGY Information Technology‟s prime concern is Information. MIS is concerned with capture, processing and communication of information. Computers thus form valuable tool in MIS.
UNDERSTANDING OF COMPUTERS The word computer comes from the Latin word “computa” which means “to calculate”. A computer is normally considered as calculating machine that can perform arithmetic operation at a very high speed. Nowadays computer is used for multiple purposes. Definition : An electronic device which is capable of performing series of arithmetic and logical operations at a very high speed is called computer. Memory is an area of computer which holds data that is waiting to be processed, Storing or output.
HISTORY OF COMPUTERS The history of computer is very old, long and fascinating. History of computer in the area of technological development is being considered because it is usually the technological advancement in computers that brings about economic and social advancement.
HISTORY OF COMPUTERS (CONTD)o A faster computer brings about faster operation and that in turn causes an economic development.o This will discuss classes of computers, computer evolution and highlight some roles played by individuals in these developments.o This emphasizes the need to study history of the computer because a proper study and understanding of the evolution of computers will undoubtedly help to greatly improve on computer technologies.
COMPUTER GENERATION In 1930, Analog computer were introduced. In 1944, H. Aiken at Hayward University USA, developed Mark-1. It was the first digital computer from IBM. Which spanned 51 feet in length and 8 feet in height. 500 meters of wiring were required to connect each component. If we consider the Generation 0 of computers till 1944, then computer were mainly special purposes. They were usually designed to do calculation work. After 1944, people concentrated on the development of general purpose computers which could be used for multiple tasks which are discussed as follow.
COMPUTER GENERATION SYSTEM First Generation (1946-59) Second Generation(1957-64) Third Generation(1965-70) Fourth Generation(1970-90) Fifth Generation(1990 till date)
FIRST GENERATION The first general purpose computer of this generation was constructed in 1946, at the Moore School of Engineering of the University of Pennsylvania, USA by Prof: Presper Eckert and John Mauchly. The name of that computer was ENIAC. Work on ENAIC started in 1943 and the project was completed in 1946. In this computer system Vacuum tubes were used. These tubes were very large in size, due to which the size of computer of that generation was large. A device to amplify, switch, or modify a signal (by controlling the movements of electrons)
SECOND GENERATION In second generation a new device was discovered, which is called transistor.a) Transistor is a small electronic device used in computers, radios, televisions, etc for controlling an electronic current as it passes along a circuit.b) Transistor were prepared by a British Scientist William Shockley. These transistor were able to move an electronic charge.Eg : Lower power consumption, smaller, more reliable, cheaper, much lower heat dissipation During this generation two programming languages were prepared. i.e.a) FORTRAN which prepared in 1956 by an American Scientist John Backus.b) COBOL which was prepared by an American women Grace Hopper in 1959. Computer of second generation are smaller in size then 1st generation computer.
SECOND GENERATION (CONTD) IBM IBM7094: For scientific application (1962) IBM1401: For business applications (1959) In 2nd generation, Increase the performance and capacity was found Lowered cost Speed increase as well All this improvement was the result of use of transistor in place of vacuum tubes.
THIRD GENERATION In this generation microelectronics were introduced which was the invention of Integrated Circuits (IC‟s). The 3rd generation was based on IC technology. IC is a small Microchip that contains a large number of electrical connections and performs the same function as a larger circuit made from separate parts. IC was an advance electronic technology, when a large number of circuit elements are integrated into a very small surface of silicon known as “Chip” then it is called an IC. IBM System/360 were the first computers to be built entirely with ICs.
THIRD GENERATION (CONTD) Computer of 3rd generation is smaller in size as compared to previous generation computer. Maintenance cost was low because the chance of hardware failure was minimum in those computers. The disadvantage of 3rd generation computer was, a very costly technology required for the manufacturing of IC chip. Cray-1: $8.8 million, 160 million instructions per seconds and 8 Mbytes of memory
FORTH GENERATION Improvements to IC technology made it possible to integrate more and more transistors in a single chip In 1970‟s SSI, MSI, LSI and VLSI circuits were used at the place of IC‟s. They are also a single silicon chips. SSI (Small Scale Integration): 10-100 MSI (Medium Scale Integration): 100-1,000 LSI (Large Scale Integration): 1,000-10,000 VLSI (Very Large Scale Integration): >10,000 The important point is that with VLSI it became possible to have a full CPU on a single chip, also called a microprocessor. The first microprocessor was created by Intel in 1971.
FORTH GENERATION (CONTD) So 4th generation computers are those which uses LSI technology, due to this technology the size of computers becomes very small but highly costly technology is required for the manufacturing of LSI chips. With the advent of microprocessors it became possible to build “personal computers” 1977: Apple II 1981: IBM PC
FIFTH GENERATION The computers that used today belongs to the fifth generation computers which performs parallel processing, multi-tasking simultaneously. Voice Recognition Artificial Intelligence Natural Languages Simulation A computer simulation is an attempt to model a real-life situation on a computer so that it can be studied to see how the system works. Computers of fifth generation are nearly capable to behave like human beings. These machine are usually equipped with a large main memory. Software and hardware components have become cheaper The size of computer in 5th generation has become surprisingly small.
CLASSIFICATION OF COMPUTERS Computing machines can be classified in many ways and these classifications depend on their functions and definitions. They can be classified by the technology from which they were constructed, the uses to which they are put, their capacity or size, the era in which they were used, their basic operating principle and by the kinds of data they process. Following are the main types of Computers :-
1. SUPER COMPUTERS Super computers are used in applications like defence, spaceexploration, industrial R&D, manufacturing etc,The supercomputers are the biggest and fastest machines today andthey are used when billion or even trillions of calculations arerequired.Super computers have capabilities far beyond even the traditionallarge-scale systems, their speed ranges from 100 million-instruction-per-second to well over three billion.For this reason, supercomputers may need the assistance of amedium-size general purpose machines (usually called front-endprocessor) to handle minor programs or perform slower speed orsmaller volume operation.
2. MAINFRAME COMPUTERS Mainframe computers are used for larger business application. They are relatively slower and smaller than super computers, thussuiting the budget of larger organization. They are used in business application were originally designed tohandle the data processing requirements such as payroll, inventorycontrol & management etcThey are used in complex modeling, or simulation, businessoperations, product testing, design and engineering work and in thedevelopment of space technology.Large computers can serve as server systems where many smallercomputers can be connected to it to form a communication network.
3. MINI COMPUTERSIn the 1960s, the growing demand for a smaller stand-alone machinebrought about the manufacture of the minicomputer, to handle tasks thatlarge computers could not perform economically.Minicomputer systems provide faster operating speeds and largerstorage capacities than microcomputer systems.Operating systems developed for minicomputer systems generallysupport both multiprogramming and virtual storage.This means that many programs can be run concurrently.This type of computer system is very flexible and can be expanded tomeet the needs of users.
4. MIRCO COMPUTERSLarge-scale production of silicon chips began in 1971 and this hasbeen of great use in the production of microcomputers.The Microcomputer has the lowest level capacity, the machine hasmemories that are generally made of semiconductors fabricated onsilicon chips.The microcomputer is a digital computer system that is controlled by astored program that uses a microprocessor, a programmable read-onlymemory (ROM) and a random-access memory (RAM).Microcomputers have from 4k to 64k storage location and are capableof handling small, single-business application such as sales analysis,inventory, billing and payroll.
HARDWARE & SOFTWARE The term hardware and software refers to the tangible & Intangible aspects of computers. The physical parts of the computers are termed as “Hardware”. The instructions necessary to make the physical parts perform are called “Software”.
HARDWAREComputer hardware refers to the actual, tangible physical parts ofthe computers, it can be studied according to its functions itperforms such as : Input Device Output Device Storage Device & The Central Processing Unit
INPUT DEVICE This device is responsible for entering data and commands into the computer. As computers developed, other forms of data storage to necessitating the input devices such as magnetic tape readers. As technology improved better & easier to use input devices such as the keyboard, mouse and scanner bar code readers etc Today, sophisticated input devices like digital cameras and webcams have become available even to home computer users.
OUTPUT DEVICE This device are capable of outputting the processed information. The need to produce output in more readable form saw the development of printers, which could be in words diagrams & pictures. The need for immediate output which need not be preserved, as well as need to be able to monitor the processing led to the development of the VDU (Visual Display Unit) Monitors of toady are capable of showing high resolution photographs & paintings.
STORAGE DEVICE & CENTRAL PROCESSING UNIT When the data has to be stored for later inputs into another process, it can be output to media like magnetic disk tape CD ROMS etc such are called “Storage Device.” Hard disk that can store larger amounts of data in random order, enabling faster access to a particular bit of data that might needed without having to read all data on the disk first. Central processing unit (CPU) is the process the data into information according to the instructions (programs) given either by direct input (keyboard, mouse) or from external media such as magnetic disk. CPU is further divided into (CU) control unit and (ALU) arithmetical and logical unit.
SOFTWARESoftware is the intangible part of computer, it consists of a set ofinstructions that tell the what to do.A set of instruction is called a Program and A set of program is calledPackage, and the sum total of the programs and packages used oncomputer is called “Software.”Some of the examples of application software are : Payroll Processing Software Inventory Control Software Accounting Software
PACKAGESA package, in computer terminology, is a set of program that can simplybe installed on a computer and used right away.Software houses realised that most business needed the same basic set ofprogram with the slight modifications to suit their specific needs. Some common packages are : Word Processing packages Spreadsheet Packages
WORD PROCESSING PACKAGES AND SPREAD SHEET PACKAGES WPP refers to the input, formatting storage and printing to text, it also includes used to write letters, memos article report etc Most WPP provide features such as Page layout, automatic pagination, columnar formatting and storage of documents as files in computer system. Spreadsheet packages offer quick & convenient ways to perform calculations using larger number of variables. Spreadsheet packages also offers features like automatic generation of graph & pie charts printing of individual parts of spreadsheet or entire spreadsheet etc who need to work with numbers.
DATABASE MANAGEMENT SYSTEM Database management systems help the user to enter, store, retrieve, format and print- cords related to individuals that form a part of a specific data base.Eg : Package may be used to store employee code records. Data package have evolved into sophisticated relational database management packages, where data from different tables can be accessed and combined to create cross- ferenced reports. The data entered can be combined into reports for management use.
DESKTOP PUBLISHING Desktop publishing, referred to as DTP, is another powerful package developed on PC‟s. Desktop publishing tools offer tools to make professional looking documents and presentations integrating text and images. The concept of WYSIWIG (What You See Is What You Get) makes it easy for the user to lay his documents out exactly the way he wants it printed. This is a very useful tool in preparing reports, presentations, training manuals, etc and such packages are widely used by professionals in these fields.
COMPUTER SYSTEM CONFIGURATIONConfiguration refers to the rating, capacity and functionally of criticalparts of computers.Some of the important components in computers configuration are asfollow:A. The ProcessorB. The RAM or Random Access MemoryC. The Hard DiskD. The Monitor or VDU (visual display unit)
A. THE PROCESSOR B. THE RAM RANDOM ACCESS MEMORY1. The is the brain of computer and most common processor are Intel Processors, the current rage being the Intel Pentium 4 processor, which of course will soon give way to another.2. The faster computer will function, and the smoother will the graphics be, clock speed (measured in Megahertz or MHz) is another important factor in selection a processor.1) RAM is another important factor in configuration of the computer & also refers to the working memory of the computer.2) The maximum amount that can be stored in the temporary memory of the computer while performing calculations, and Moderns programs & packages especially use GUI (Graphic User Interface) are memory-hungry programs/packages need larger amount RAM function properly.
C. THE HARD DISKD. THE MONITOR OR VDU (VISUAL DISPLAY UNIT)1. Just like RAM, the larger the hard disk capacity, the better off one is in the long run.2. Hard disk capacity is now measured in Gigabytes or GB, where 1GB equals to 1000 megabytes.1) While the size or type of monitors may not have direct bearing on the processing speed of the computer, it does play an important role in the presentation of data.2) Computers are used to display graphics or images such as Drawings & photograph and has to be compatible with rest of system to provide smooth operation.
DATA PROCESSINGData processing refers to the collection, capture, storage & combinationof data into useable results.In computer system, data is input & information is the output, theconversation of data into useful information is called Processing.Data: Data refers to individual elements which by themselves areincapable of providing a basis for decision making.Information: Information is the basis on which decision can be madeand information is produced by combining data & formatting the resultinto a usable form.
TYPES OF DATA PROCESSINGData processing is essentially of 3 types:I. Batch ProcessingII. On-line ProcessingIII. On-line Real Time Processing
A. BATCH PRODUCTION Batch production refers to the collection of data different times within a period & processing that data in the batch at specified intervals or at the end of the time period. B. ON-LINE PRODUCTION The data is processed immediately upon the occurrence of the transaction is called on-line processing. Most companies use a combination of Online and Batch processing, depending on their requirements. C. Online Real Time Processing Information required to be processed immediately, that result too have to be produced at the end of the transaction is called online real time processing.
TRANSACTION PROCESSINGI. Transaction Processing refers to the different kinds like cash payments, reimbursement to employees, financial transaction etcII. Transaction Processing is one of the most common forms of processing in the business organization DISTRIBUTED PROCESSINGI. This form of processing refers the setting up of smaller processing units throughout the organization, which are linked through networking to each other through central computer called Server.II. Distributed processing also has its unique set of problems, which, may allow different departments to apply their own parameters o report formats, programs used validation exercises etc.
VALIDATION AND CONTROLS No matter how sophisticated a computer, it can be as accurate as the data that fed in Garbage In Garbage Out or (GIGO) is basic concept that needs to be absorbed by every user, manager and system professionals. Some of the Input Errors:1. Transposition Error: In this type of error, two digits in a number may be „transposed‟2. Transcription Error: It refers to where a number or letter is misread by the operator.3. Random Error: In this type of error, the number entered is completed erroneous.
CONTOLLING INPUT ERRORS Input errors can be controlled by several means, depending the nature of data, this is called Validation. Validation checks can be built into the input program, so that common errors are minimized or eliminated completed.The second type of error that may in occur in system is a Processor error A processor error occurs when the output of one process is passed on to another process as input. Processor controls are used to ensure that all of the relevant output is indeed passed on to the next process. If the system accepts such erroneous data, validation checks have to be put in to prevent input of such erroneous data.