Computer generations can be divided into five periods based on the underlying technologies used: First generation computers (1940-1958) used vacuum tubes and were enormous in size, occupying entire rooms. The second generation (1959-1964) replaced vacuum tubes with transistors. The third generation (1964-1974) saw the development of integrated circuits and silicon chips, which allowed computers to be smaller and interface with keyboards, monitors, and operating systems. The fourth generation (1975-1989) introduced microchips and microprocessors. The fifth generation (1990-present), still in development, aims to develop artificial intelligence capabilities like natural language processing and self-learning.

1. Computer Generations

2. Computer Generations
• Term generation indicates the type of technology
used in the computer construction.
• The new technology improved the speed,
accuracy and storage capacity of the computers.
Two Eras:
• Mechanical Era (Before 1940)
• Electronic Era (Since 1940)

3. Computers can be divided into five generations
depending upon the technologies used. These
are:
• First Generation (1940 - 1958)
• Second Generation (1959 - 1964)
• Third Generation (1964 - 1974)
• Fourth Generation (1975 - 1989)
• Fifth Generation (1990 - Present)

4. First Generation 1940- 1956
• Used vacuum tubes for circuit.
• Enormous size and took up entire room.
• Relied on machine language.
• Used a great deal of electricity, generated a lot
of heat.
• Hard-wired.
• IBM 650, Univac I, ENIAC, EDVAC

5. Second Generation 1959-1964
• Transistors replaced vacuum tubes.
• Transistor was invented in 1948 at Bell
Laboratories.
• Computers moved from cryptic binary machine
language to symbolic(Assembly Language).
• Punch Cards & Paper.
• Honeywell 400, IBM 7030, UNIVAC LARC, CDC
1604

6. Third Generation 1965-1974
• Development of the Silicon Chips (Integrated
circuits)= IC
• Initially, an IC contained only about ten to twenty
components (Small Scale Integration (SSI)).
• Transistors were miniaturized and placed
on silicon chips, called semiconductors.
• Used keyboards and monitors and interfaced
with an operating system.

7. Third Generation 1965-1974(Contd.)
• High-level languages were commonly used,
such as early versions of COBOL
and FORTRAN.
• IBM 360/370, PDP-8,11, CDC 6600.

8. Fourth Generation 1975-1989
• Microchip technology was introduced
• LSI (Large Scale Integration) chips were
developed.
• It was possible to integrate over 30,000 or more
components on to single LSI chip.
• VLSI was also developed.

9. Fourth Generation 1975-
1989(Contd.)
• Development of microprocessor.
• Used advanced input & output devices.
• IM PC & its clones, Apple II, CRAY-1, CRAY-2.

10. Fifth Generation 1990-present
• First to fourth generation computers did not have
their own thinking power.
• Based on artificial intelligence (AI).
• The goal of fifth-generation computing is to
develop devices that respond to natural
language input and are capable of learning and
self-organization.
• ULSI Technology has to be used.

11. Fifth Generation 1990-present
(Contd.)
• Are still in development, though there are some
applications, such as voice recognition.
• The programming languages LISP (List
Processor) and PROLOG (Programming with
Logic) are used for artificial intelligence.

12. Thank You