Fourth Generation Computers (1971-Present)

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 1980's, 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 automobiles with electronic fuel injection incorporat­ed microprocessors.

Such condensed power allowed everyday people to harness acom­puter's power. They were no longer developed exclusively for large busi­ness or government contracts. By the mid-1970's, 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. Pioneers in this field were Com­modore, Radio Shack and Apple Computers. In the early 1980's, arcade video games such as Pac Man and home video game systems such as the Atari 2600 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 1980's 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 IBM's PC was Apple's 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 one's 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. Using either direct wiring, called a Local Area Network (LAN), or telephone lines, these networks could reach enormous proportions. A global web of computer circuitry, the Internet, for example, links computers world­wide into a single network of information. During the 1992 U.S. presi­dential election, vice-presidential candidate Al Gore promised to make the development of this so-called " information superhighway" an ad­ministrative priority. Though the possibilities envisioned by Gore and others for such a large network are often years (if not decades) away from realization, the most popular use today for computer networks such as theInternet is electronic mail, or E-mail, which allows users to type in a computer address and send messages through networked ter­minals across the office or across the world.