Information Technology

Information Technology (IT) is the technique used in Information System. An information system collects, processes, stores, analyzes and disseminates information for a specific purpose. Communication is the backbone of IT. IT can be defined as the implementation of Information Science where Information Science is a set of algorithms, principles, and theories. Computer System, Internet, Telecommunication systems are the information technology we use.

Information systems are scattered throughout organizations, often in several locations and sometimes in two or more organizations. IT is implemented here to relay the information between these locations. Not only the organization but also the individual today is dependant on IT for career development and education. Education Institutions today provide distance education and online examinations. GIS has emerged due to the development of IT. Scientists now can acquire geographical information from the satellites.

Evolution of Information Processing

Information Processing evolved due to the growth of national and international organizations. Since the early computing days, as costs declined and computer technologies improved, computers have been used to support managerial and other organizational activities of every sort.

Scopes/ Application field of Information System

• Telecommunication
• Internet
• GIS
• Education
• Security System
• E-Governance
• Medicine
• Scientific Research

Introduction to Computers

A computer is a programmable electronic machine. It takes raw facts as input, process these and gives the final output which is the result of processing. It responds to a specific set of instructions in a well-defined manner. It can execute a prerecorded list of instructions (a program).

Digital and Analog COmputer

A Digital Computer is a device capable of processing information in discrete form. It means it performs calculations and logical operations in the binary system i.e. using the digits 0s and 1s. Modern-day computers are digital computers.

An analog computer is a computer that stores data in a continuous form of physical quantities and performs calculations with the help of measures. These are the earliest machines used for analog computation and process controls. Generally, they are used to measure parameters such as temperature, pressure, voltage, and speed that changes continuously with time. Slide rules and nomograms are examples of analog computers.

Classification of Computers (Types of Computers)

1. Super Computers

• They are the computers with the most processing power. The primary application of supercomputers has been in scientific and military work, but their use is growing in business as their prices decreases They are especially valuable for large simulation models of real world phenomena, where complex mathematical representations and calculations are required or for image creation and processing. They are also used in weather prediction, design aircraft( Boeing 777), motion picture like star wars and Jurassic Park). They operate generally at 4 to 10 times faster than the next most powerful computer class, the mainframe.

2. Maniframe Computers

They are less powerful and generally less expensive than supercomputers. Large corporate use mainframe computers for centralized data processing maintaining large databases. Application than run on a mainframe can be large and complex, allowing for data and information to be shared throughout the organization. Examples: Airline Reservation System, Corporate Payroll, Student Information etc. A mainframe system may have anywhere from 50megabytes to several gigabytes of primary storage. Secondary storage may use high capacity magnetic and optical storage media with capacities in the gigabytes to terabyte range. Typically, several hundreds or thousands or online computers can be linked to a mainframe. Advance mainframe performs more than 1,000 MIPS and can handle up to one billion transactions per day.

3. Mini Computers

Also called midrange computers, are relatively small, inexpensive and compact computers that perform the same functions as mainframe computers but to limited extent. They are designed specially for accomplishing specific tasks such as process control, scientific research, and engineering applications. IBM is the market leader in minicomputers with its AS/400 series of computers. Larger companies gain greater corporate flexibility by distributing data processing with minicomputers in organizations units instead of centralization at one place. They form the network.

4. Workstations

Computers vendors originally developed desktop engineering workstations or to provide the high levels of performance demanded by engineers. They are based on RISC (Reduced Instruction Set Computing) architecture and provide both very high speed calculations and high resolution graphic displays. The distinction between workstation and personal computers is rapidly blurring. The latest PC has the computing power of recent workstation.

5. Micro Computers

These are also called PCs and are the smallest and least expensive category of general purpose computers. Micro computer ranges from palmtops to Desktop computers. Laptops/ Notebooks are very popular now a day. Microprocessor is the core part of the Micro computers which forms the CPU.

History: from Pascaline to the first generation of computers

Pascaline

In 1642, 19 year old French mathematician Blaise Pascal invented a mechanical adding machine called Pascaline. The numbers were entered by means of add and subtract. It had 8 wheels and each wheel had 10 digits from 0 to 9.

Stepped Recknor

In 1671, German mathematician Gothfried von Leibnitsz invented an improved and strong computing machine called “stepped Recknor” which could multiply, divide and workout square roots apart from addition and subtraction. The machine also had handle and gear.

Analytical Engine

In 1833, Charles Babbage, (English mathematician) developed Analytical Engine which was a kind of a general purpose computer designed to solve any arithmetical problems. It was significant in a way that it had most of the elements present in today‟s digital computer systems, that‟s why he‟s called “Father of modern computer science.”

Lady Ada Augusta, disciple of charles Babbage, after his demise developed several programs for performing mathematical calculations on Analytical engine. She is considered as the first programmer in history and has to her credit a computer language called ADA named after her.

Dr. Herman Hollerith

In 1890AD, Herman Hollerith designed a system to record census data. The information was stored as holes in punched cards, which were interpreted by machines with electrical sensors.

Mark-I

In 1944 Howard Aiken completed mark I. It was an electromechanical computer which was 51ft. long, 8 ft. height, and 3 ft wide and consisted of 18000 vacuum tubes. This consisted of 7 lakh 50 thousand parts and 500 miles long wire.

Electronic Numerical integration and calculator (ENIAC) – 1946 A.D.

ENIAC was the first electronic computer developed by John Mauchly and John presper Eckret in 1946. It could do 5000 additions per second. It was extremely huge, used 19,000 vacuum tubes, occupied an area of 150 sq. meters, weighed about 30 tons and required about 130 kW of power.

EDVAC

In 1952, Electronic Discrete Variable Automatic Computer (EDVAC) was developed by John Mauchly and John Presper Eckert with the help of A. Burks and Neumann. This machine was used to store the data and information as well as the instructions.

• John Mauchly and Eckert founded their own company in 1946 and began to work on Universal Automatic Computer (UNIVAC): general purpose commercial computer in 1951. It was the first commercially used electronic computer in the world.
• In 1958, the first computer to use the transistor as a switching device, the IBM 7090, was introduced.
• In 1964, the first computer to use Integrated circuits (IC), the IBM 360 was announced.
• In 1975, the first microcomputer, the Altair, was introduced. In the same year, the first Supercomputer, the Cray-1 was announced.

The Computer System

The central processing unit (CPU) is the core computing part of a computer. It comprises an arithmetic logic unit (ALU) for calculation, the main memory unit (MMU) to temporarily store the data for processing and a control unit to control the flow of data between memory, input/output sources, and ALU. The computer is fully functional with peripheral devices like keyboard, trackpad, mouse, and monitor. This is the hardware component of a computer system.

How to perform certain operations is defined by a set of logical statements commonly referred to as software which is another essential part of the system. This could be a system software that is essentially required for the computer to operate, an example can be considered as operating system software. The other is an application software which is used to perform a dedicated task. Like a paint program is used to draw on a canvas or a text editor is used to write and store some texts.

Another component of the computer system is data. It is information provided as input to the computer, which is processed to generate some meaningful information.

Users are also known as Liveware, orgware, or humanware and are also the component of a computer system. The user writes computer software programs and commands the computer to execute the instructions.

So, the computer system is comprised of Hardware, Software, Data, and User.

Functions and Components of a Computer

To function properly, the computer needs both hardware and software. Hardware consists of the mechanical and electronic devices, which we can see and touch. The different parts of the computer are Processor (CPU), Input devices, Output devices, Storage devices and Memory devices. The software consists of programs, the operating systems and the data that reside in the memory and storage devices.

A computer does mainly the following four functions:

• Receive input – Accept information from outside through various input devices like the keyboard, mouse, etc.
• Produce information – Perform arithmetic or logical operations on the information.
• Produce output – Communicate information to the outside word through output devices like monitor, printer, etc.
• Store information – Store the information in storage devices like hard disk, floppy disks, etc

Computer hardware falls into two categories: processing hardware, which consists of the central processing unit (CPU), and the peripheral devices. The CPU, as its name implies, is where the data processing is done. Peripheral devices allow people to interact with the CPU. Together, they make it possible to use the computer for a variety of tasks.

Input/Output (I/O) Unit: The I/O unit is used to interact with the computer. The input unit accepts data from user and sends to the computer for further processing while the output unit is used to show result of the perfomed operation based on the instruction provided by the user. Commonly used input devices are mouse, keyboard, scanner, trackpad and output devices are monitor and printer.

Central Processing Unit (CPU): CPU is considered as the brain of the computer. CPU is rensopnsible to control, coordinate and supervise the operation of a computer. It is composed of arithemetic logic unit (ALU), control unit (CU) and memory unit. ALU performs all the logical and arithemtic operation while control unit is reposible to manage data flow between ALU and memory unit.

Main Memory Unit: MMU are also called as primary memory of the computer. It used to store temporary data, instructions, addresses and intermediate results of calculations.