Generations of Computers Lecture # 02 Instructor: Naveedullah Safi

ZEROETH GENERATION Man used his fingers, ropes, beads, bones, pebbles and other objects for counting. Abacus, Pascaline, Difference & Anylitical engines Electricity was not yet invented Abacus a simple device for calculating, consisting of a frame with rows of wires or grooves along which beads are slid The Pascaline was the first successful mechanical calculator. It was developed in the 1640's by the mathematician Blaise Pascal The Analytical Engine was a proposed mechanical general-purpose computer designed by English mathematician and computer pioneer Charles Babbage. It was first described in 1837 as the successor to Babbage's difference engine, a design for a mechanical computer

pascaline Abacus

First generation computers (1940-1956) The first computers used vacuum tubes for circuitry and magnetic drums for memory. These tubes, like electric bulbs, produced a lot of heat Punched cards, paper tape, and magnetic tape were used as input and output devices  They were very large in size and taking up entire room. The computers in this generation used machine code as programming language..

The main features of first generation are: Vacuum tube technology Unreliable Supported machine language only Very costly Generated lot of heat Slow input and output devices Huge size Need of A.C. Non-portable Consumed lot of electricity Magnetic Drum

Some computers of this generation were: ENIAC EDVAC UNIVAC IBM-701 IBM-650 ENIAC IBM-701 UNIVAV

Second generation computers (1956-1963) In this generation transistors were used that were cheaper, consumed less power, more reliable and faster than the first generation machines made of vacuum tubes. magnetic cores were used as primary memory and magnetic tape and magnetic disks as secondary storage devices  assembly language and high-level programming languages like FORTRAN, COBOL were used.

The main features of second generation are: Use of transistors Reliable in comparison to first generation Smaller size as compared to first generation Generated less heat Consumed less electricity Faster than first generation computers Still very costly A.C. needed Supported machine and assembly languages

Some computers of this generation were: IBM 1620 IBM 7094 CDC 1604 CDC 3600 UNIVAC 1108

Third generation computers (1964-1971) The development of the integrated circuit was the hallmark شناخت of the third generation of computers.  Single IC has many transistors. Instead of punched cards and printouts, users interacted with third generation computers through keyboards and monitors and interfaced with an operating system. Allowed the device to run many different applications at one time.

Fourth generation computers (1971-present) The fourth generation computer started with the invention of microprocessor. The microprocessor contain thousand of ICs. The Intel 4004 chip, developed in 1971. It greatly reduced the size of computer. The size of modern microprocessor is usually one square inch. Fourth generation computers also saw the development of GUIs, the mouse and handheld devices.

Fourth generation computers

Fifth generation computers (present and beyond) Fifth generation computing devices, based on artificial intelligence. Are still in development, though there are some applications, such as voice recognition. The use of parallel processing is helping to make artificial intelligence a reality. The goal of fifth-generation computing is to develop devices that respond to natural language .

Fifth generation computers