History of computer

The ideas and inventions of many engineers, mathematicians, and scientists led to the development of the computer. The first true calculating machines were developed in the 1600's. In 1642, the French mathematician, scientist, and philosopher Blaise Pascal invented the first automatic calculator. The device performed addition and subtraction by means of a set of wheels linked to each other by gears. The first wheel represented the numbers 1 to 10, the second wheel represented 10's, and the third stood for 100, and so on.
The punched cards of the Jacquard loom inspired the English mathematician Charles Babbage. During the 1830's, Babbage developed the idea of a mechanical computer that he called an analytical engine.
In 1888, American inventor and businessman Herman Hollerith devised a punched card system, including the punching equipment, for tabulating the results of the United States census. Hollerith's machines used electrically charged nails that, when passed through a hole punched in a card, created a circuit. The circuits registered on another part of the machine, where they were read and recorded. Hollerith's machines tabulated the results of the 1890 census, making it the fastest and most economical census up to that date. In a single day, 56 of these machines could tabulate census information about more than 6 million people. In 1911, he sold his share of the company. Its name was changed to the Computing-Tabulating-Recording Company (C-T-R). In 1924, the name was changed to International Business Machines Corporation (IBM).
Although ENIAC worked rapidly, programming it took a great deal of time. Eckert and Mauchly next worked on developing a computer that could store even more of its programming. They worked with John von Neumann, a Hungarian-born American mathematician. Von Neumann helped assemble all available knowledge of how the logic of computers should operate. He also helped outline how stored programming would improve performance. In 1951, a computer based on the work of the three men became operational. It was called EDVAC (Electronic Discrete Variable Automatic Computer). EDVAC strongly influenced the design of later computers.
The invention of the transistor in 1947 led to the production of faster and more reliable electronic computers. Transistors soon replaced the bulkier, less reliable vacuum tubes. In 1958, Control Data Corporation introduced the first fully transistorized computer, designed by American engineer Seymour Cray. IBM introduced its first transistorized computers in 1959.
Miniaturization continued with the development of the integrated circuit (a complete circuit on a single chip) in the early 1960's. This device enabled engineers to design both minicomputers and high-speed mainframes with huge memories.
By the late 1960's, many large businesses relied on computers. Many companies linked their computers together into networks, enabling different offices to share information. The first personal computer, the Altair, was introduced in 1975. Only electronics hobbyists bought these computers.
In 1977, two young American computer enthusiasts, Steven P. Jobs and Stephen G. Wozniak, founded Apple Computer, Inc., and introduced the Apple II personal computer. The Apple II was much less expensive than mainframes. As a result, computers became available to people other than computer specialists and technicians. Personal computers were purchased by small and medium-sized businesses that could not afford mainframes or did not need the immense computing power the mainframes provided. Millions of individuals, families, and schools also bought personal computers. In 1975, former schoolmates Bill Gates and Paul Allen founded Microsoft Corporation to develop programs for the Altair. In 1981, IBM entered the personal computer market with its PC. The machine was even more successful than the Apple II. Microsoft soon was developing programs for the PC. Gates and Allen went on to become two of the world's wealthiest men. Apple scored another success in 1984 with the introduction of its Macintosh, a powerful, easy-to-use desktop computer.