The Computer And Its History Essay Research — страница 2

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noted by commercial industries and soon led to the development of improved punch-card business-machine systems by International Business Machines (IBM), Remington-Rand, Burroughs, and other corporations. By modern standards the punched-card machines slow, typically processing from 50 to 250 cards per mintue, 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. For more than 50 years following their first use, punched card machines did the bulk of the world’s business computing and a good portion of the computing work in science. (Chposky, 73) However, the punch cards had drawbacks that needed to be fixed or replaced. Electro-Mechanical and

Electrical Calculating Machines By the late 1930s punched-card machines 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 was large, 51yds in length by 8yds wide by 2yds high. The mass of metal had 3000 connections and used 450 miles of copper wiring. This massive was named the Harvard Mark I, it handled 23-digit numbers and could perform all four arithmetic operations. In addition, it had special built-in programs to handle logarithms and trigonometric functions. The Mark I was controlled from prepunched paper tape. Output was by cardpunch and electric typewriter. This was the first

printer, different from todays but did the basic job. It was slow, requiring 3 to 5 seconds for multiplication, but it was fully automatic and could complete long computations without human intervention. (Chposky, 103) The Colossus was the first known government built computer. The Colossus built by the British Secret service during World War I. It was used to break the German war codes and successful. The British knew the codes of the Germans thought the war and knew when German was going to attack and used this to a great deal to save lives. The Colossus, not only helped England in WWI but, was also used in WWII. However, did not break the codes of the Germans in that war. The British just had to wait for a better computer. The outbreak of World War II produced a desperate need

for computing capability, especially for the military. After seeing what the Colossus did for the British every had need and for a computer. New weapons systems were produced which needed trajectory tables and other essential data. (Soma, 81) 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 was thus about 1,000 times faster than the previous generation of computers.” (Dolotta, 47) ENIAC used vacuum tubes

18,000 at that, was 1800 square feet of floor space, and used 180,000 watts of electricity a day. 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 you needed the computer to do. It was, however, efficient in handling the particular programs for which it had been designed. ENIAC is generally accepted as the first successful high-speed electronic digital computer and was in many applications from 1946 to 1955. (Dolotta, 105) Mathematician John von Neumann was very interested in the ENIAC. I n 1945, he undertook a theoretical study of computation that demonstrated that a computer could have a very simple. In addition, 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 what he called “random access memory,” became fundamental for future generations of high-speed digital computers and were universally adopted.” (Hall, 73) Random Access Memory (Ram) Computers Comes into the Lime-Light The first wave of modern programmed electronic computers to take advantages of Von’s ideas 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