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Though transistors were clearly an improvement over the vacuum tube, they still generated a great deal of heat, which damaged the computers sensitive internal parts. The quartz rock eliminated this problem. Jack Kilby, an engineer with Texas Instruments, developed the integrated circuit (IC) in 1958. The IC combined three electronic components onto a small silicon disc, which was made from quartz. Scientists later managed to fit even more components on a single chip, called a semiconductor. As a result, computers became ever smaller as more components were squeezed onto the chip. Another Third Generation Computers development (1964-1971) included the use of an operating system that allowed machines to run many different programs at once with a central program that monitored and coordinated the computers memory.

Modern development of computers is usually considered as Forth Generation. After the integrated circuits, the only place to go was down in size, that is. Large scale integration (LSI) could fit hundreds of components onto one chip. By the 1980s, very large scale integration (VLSI) squeezed hundreds of thousands of components onto a chip. Ultra-large scale integration (ULSI) increased that number into the millions. The ability to fit so much onto an area about half the size of a U.S. dime helped diminish the size and price of computers. It also increased their power, efficiency and reliability. The Intel 4004 chip, developed in 1971, took the integrated circuit one step further by locating all the components of a computer (central processing unit, memory, and input and output controls) on a minuscule chip. Whereas previously the integrated circuit had had to be manufactured to fit a special purpose, now one microprocessor could be manufactured and then programmed to meet any number of demands. Soon everyday household items such as microwave ovens, television sets and cars incorporated microprocessors.

Such condensed power allowed everyday people to harness a computers power. They were no longer developed exclusively for large business or government contracts. By the mid-1970s, computer manufacturers sought to bring computers to general consumers. These minicomputers came complete with user-friendly software packages that offered even non-technical users an array of applications, most popularly word processing and spreadsheet programs. In the early 1980s, video games ignited consumer interest for more sophisticated, programmable home computers.

In 1981, IBM introduced its personal computer (PC) for use in the home, office and schools. The 1980s saw an expansion in computer use in all three arenas as clones of the IBM PC made the personal computer even more affordable. The number of personal computers in use more than doubled from 2 million in 1981 to 5.5 million in 1982. Ten years later, 65 million PCs were being used. Computers continued their trend toward a smaller size, working their way down from desktop to laptop computers (which could fit inside a briefcase) to palmtop (able to fit inside a breast pocket). In direct competition with IBMs PC was Apples Macintosh line, introduced in 1984. Notable for its user-friendly design, the Macintosh offered an operating system that allowed users to move screen icons instead of typing instructions. Users controlled the screen cursor using a mouse, a device that mimicked the movement of ones hand on the computer screen.

As computers became more widespread in the workplace, new ways to harness their potential developed. As smaller computers became more powerful, they could be linked together, or networked, to share memory space, software, information and communicate with each other. As opposed to a mainframe computer, which was one powerful computer that shared time with many terminals for many applications, networked computers allowed individual computers to form electronic co-ops like Internet.

1) What allowed microprocessors to be widely used in everyday life?

2) Which common things use microcomputers?

3) Why PCs became widespread so quickly?

4) Which companies pioneered in development of personal computers?

5) What are distinguishing features of modern PCs?

6) What generation of computers followed the Forth Generation?

Date: 2015-12-11; view: 100

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