Only once in a lifetime will a new invention come about to touch every aspect of our lives. Such a device that changes the way we work, live, and play is a special one, indeed. A machine that has done all this and more now exists in nearly every business in the U.S. and one out of every two households (Hall, 156). This incredible invention is the computer. The electronic computer has been around for over a half-century, but its ancestors have been around for 2000 years. However, only in the last 40 years has it changed the American society. From the first wooden abacus to the latest high-speed microprocessor, the computer has changed nearly every aspect of people's lives for the better. The very earliest existence of the modern day computer's ancestor is the abacus which date back to almost 2000 years ago. The first major use for a computer in the U.S. was during the 1890 census. Two men, Herman Hollerith and James Powers, developed a new punched-card system that could automatically read information on cards without human intervention (Gulliver, 82). Since the population of the U.S. was increasing so fast, the computer was an essential tool in tabulating the totals. These advantages were noted by commercial industries and soon led to the development of improved punch-card business-machine systems by IBM Remington-Rand, Burroughs, and other corporations. By modern standards the punched-card machines were extremely slow, typically processing from 50 to 250 cards per minute, with each card holding up to 80 digits. At the time, however, punched cards were an enormous step forward; they provided a means of input, output, and memory storage on a massive scale. By the late 1930s punched-card machine techniques had become so well established and reliable that Howard Hathaway Aiken, in collaboration with engineers at IBM, undertook construction of a large automatic digital computer based on standard IBM electromechanical parts. Aiken's machine, called the Harvard Mark I, handled 23-digit numbers and could perform all four arithmetic operations. Also, it had special built-in programs to handled logarithms and trigonometric functions. The Mark I was controlled from prepunched paper tape. Output was by card punch and electric typewriter. It was slow, requiring 3 to 5 seconds for a multiplication, but it was fully automatic and could complete long computations without human intervention (Chposky, 103). The outbreak of World War II produced a desperate need for computing capability, especially for the military. New weapons systems were produced which needed trajectory tables and other essential data. In 1942, John P. Eckert, John W. Mauchley, and their associates at the University of Pennsylvania decided to build a high-speed electronic computer to do the job. This machine became known as ENIAC, for "Electrical Numerical Integrator And Calculator". It could multiply two numbers at the rate of 300 products per second, by finding the value of each product from a multiplication table stored in its memory. ENIAC used 18,000 standard vacuum tubes, occupied 1800 square feet of floor space, and used about 180,000 watts of electricity. It used punched-card input and output. The ENIAC was very difficult to program because one had to essentially re-wire it to perform whatever task he wanted the computer to do. It was, however, efficient in handling the particular programs for which it had been designed. In 1945 Mathematician John von Neumann undertook a theoretical study of computation that demonstrated that a computer could have a very simple and yet be able to execute any kind of computation effectively by means of proper programmed control without the need for any changes in hardware. Von Neumann came up with incredible ideas for methods of building and organizing practical, fast computers. These ideas, which came to be referred to as the stored-program technique, became fundamental for future generations of high-speed digital computers and were universally adopted (Hall, 73). The first wave of modern programmed electronic computers to take advantage of these improvements appeared in 1947. This group included computers using random access memory (RAM), which is a memory designed to give almost constant access to any particular piece of information (Hall, 75). These machines had punched-card or punched-tape input and output devices and RAMs of 1000-word capacity. Physically, they were much more compact than ENIAC: some were about the size of a grand piano and required 2500 small electron tubes. This was quite an improvement over the earlier machines. The first-generation stored-program computers required considerable maintenance, usually attained 70% to 80% reliable operation, and were used for about 8 to 12 years. Typically, they were programmed directly in machine language. The UNIVAC, which was the first commercially available computers (Hazewindus, 102) was developed by John W. Mauchley and John Eckert, Jr. in the 1950's.
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