FOURTH GENERATION(1972-1984)

Introduction In this generation, there were developments of large-

scale integration or LSI (1000 devices per chip) and very large-scale integration or VLSI (10000 devices per chip). These developments enabled the entire processor to fit into a single chip and in fact, for simple systems, the entire computer with processor; main memory and I/O controllers could fit on a single chip.

Core memories now were replaced by semiconductor memories and high-speed vectors dominated the scenario

 Names of few such vectors were Cray1, Cray X-MP and Cyber205.

Fourth Generation Integrated Circuits

Fourth Generation Integrated Circuits

FOURTH GENERATION TIMELINE

1976 19791975

1981 19821980

19841983

1975• MITS, inc. advertises one of the first

microcomputers, the Altair. Named for the destination in an episode of Star Trek, the Altair is sold in kits for less than $400. Although initially it has, no keyboard, no monitor, no permanent memory, and no software, 4200 orders are taken within the first three months.

ALTAIR

1976• Steve Wozniak and Steve Jobs. Founder

of Apple Computers and engineer invented one of the first computers Apple II, is an immediate success. Adopted by elementary school, high school, and colleges, for many students the Apple II is their first contact with the world of computers.

APPLE II

1979• VisiCalc was the first computer

spreadsheet program. It was released to the public in 1979, running on an Apple II computer. While BASIC and few games had quickly supported most early microprocessor computers, VisiCalc introduced a new level in application software. It was considered a fourth generation software program.

1980• IBM hires Paul Allen and Bill Gates to create an

operating system for a new PC. The pair buy the rights to a simple operating system manufactured by Seattle Computer Products and use it as template. IBM allows the two to keep the marketing rights to the operating system, called DOS.

• The programming language FORTRAN 77 is created.

Bill Gates & Paul Allen

1981• IBM offers Microsoft Corporation co-

founder Bill Gates, the opportunity to develop the operating system for the soon to be announced IBM personal computer. With the development of MS-DOS.

1982• Compaq Computer was reformed in 1982

and their first product announced in November 1982 was the Compaq Portable. The company even derived its name from the “compact” nature of this machine.

1983• Lotus Software (called Lotus Development

Corporation before its acquisition by IBM) is an American software company headquartered in Cambridge, Massachusetts.

• On November 10.1983, at the Plaza Hotel in New York City, Microsoft Corporation formally announced Microsoft Windows.

1984• Apple introduces the Macintosh computer,

which incorporates a unique easy-to-learn, graphical user interface. At the same year Hewlett Packard Company announces the first LaserJet printer for personal computers.

Macintosh