First Generation: 1951-1958

Improvements in computer capabilities are grouped in generations based upon the electronic technology available at the time. The first generation of computers -based upon the designs of the ENIAC and EDVAC- began with the sale of the first commercial electronic computer. This machine, called the UNIVAC I, was developed by Mauchly and Eckert, who had approached Remington Rand for financing. Remington Rand (later Sperry Corporation) bought Mauchly and Eckerr's company and propelled itself into the computer age with a product that was years ahead of the machines produced by competitors. In 1951, the first UNIVAC I replaced IBM equipment at the U.S. Census Bureau. Another UNIVAC was installed at General Electric's Appliance Park in Louisville, Kentucky. For the first time, business firms saw the possibilities of computer data processing.

The UNIVAC I and other first-generation computers were huge, costly to buy, expensive to power, and often unreliable. They were slow compared to today's computers, and their memory capacity was limited. They depended upon the first-generation technology of vacuum tubes for internal operations. The masses of vacuum tubes took up a lot of space and generated considerable heat, requiring an air-conditioned environment. Vacuum tubes could switch on and off thousands of times per second, but one tube would fail about every fifteen minutes. Too much time was wasted hunting for the burned-out tubes (see picture below).

Punched cards were used to enter data into the machines. Memory consisted of magnetic drums, cylinders coated with magnetizable material. A drum rotated at high speeds while a device was poised just above it either to write on the drum by magnetizing small spots or to read from it by detecting spots already magnetized. Then results of processing were punched on blank cards.

Early first-generation computers were given instructions coded in machine language, that is, a code that designates the electrical states in the computer as combinations of 0's and 1's. Preparing the program or instructions was extremely tedious and errors were common. In order to overcome the difficulty, symbolic languages were developed. Symbolic languages use mnemonic symbols to represent instructions. For example, ADD would stand for addition. These symbols were easier for people to use than the strings of 0's and 1's of binary code, but the computer had to translate each symbol into machine language. A special set of language-translator programs was developed for this job. Rear Admiral Grace Murray Hopper of the U.S. Navy worked with a team that developed the first of these programs.

In the early 1950s, the public was not yet aware of the amazing computing machines. This changed with the 1952 presidential election. After analyzing only 5 percent of the tallied vote, a UNIVAC I computer predicted that Dwight David Eisenhower would defeat Adlai E. Stevenson. CBS doubted the accuracy of the prediction and did not release the information to the public until the election results were confirmed by actually counting the votes. The electronic prediction became the first in a burgeoning trend that has culminated in today's controversy about predicting election results from East Coast tallies before polls are closed on the West Coast.

Business acceptance of computers grew quickly. In 1953, Remington Rand and IBM led the infant industry, having placed a grand total of nine installations. But by the late 1950's, IBM alone had leased one thousand of its first-generation computers.

Last Updated Jan. 5/99