Chapter 1. Computers
Pinning down the meaning of a word is devilishly difficult, particularly when it's used by a sideshow huckster, lawyer, or some other professional liar. Definitions vary not only with who is speaking, but also when. Language evolves and meanings shift. Words often go to extremes, shifting meanings even to opposites ”cold becomes hot, bad becomes good, and rap becomes popular.
is one of those shifty words. Exactly what makes up a computer depends on who you are and when you're talking about. Today a computer is something you can hold in your hand or at least lift with your hands. Thirty years ago, you would have needed a hand from a friend or two to roll a computer machine around. Sixty
Computers in History
Strictly speaking, a computer is something that computes, which is not a particularly informative definition. In the vagueness of the
Up until the end of World War II, a computer was a person who computed. She might use a pencil (a pen if she were particularly confident of her results), a slide rule, or even a mechanical calculator . Poke a few numbers in, pull a crank, and the calculator machine printed an answer in purple ink on paper tape ”at least if the questions involved simple arithmetic, such as addition. If this person did a lot of calculations, the black ink of the numbers soon faded to a pale gray, and he grew calluses on his fingertips and cranking hand.
The early machines for mathematics were once all known as
was first applied to machines after electricity
The first of these machines ”a mechanical computer of which Babbage would have been proud ”was the IBM-financed Automatic Sequence Controlled Calculator, which is often called Harvard Mark I. The five-ton design included 750,000
Many of the fundamentals of today's computers first took form in the partly electronic, partly mechanical machine devised by John Vincent Atanasoff at Iowa State College (now University). His ideas and a prototype built with the aid of graduate student Clifford Berry have become a legend known as the Atanasoff Berry Computer (with the acronym ABC), the first electronic digital computer ”although it was never contemporaneously called a "computer." Iowa State called the device "the world's
In Britain, crypto-analysts developed a vacuum-tube ( valve in Britain) device they called Colossus that some people now call the first electronic computer ”usually British folk who don't want you to forget that the English can be clever, too. But the rest of the world never called Colossus a computer ”or anything else ”because it was top secret until the end of the century.
The present usage of the word
goes back only to June 5, 1943, when ENIAC (the most complex vacuum tube-based device ever made) was first proposed as a collaboration between the United States Army and the University of Pennsylvania. The original agreement on that date first used the description that became its name, as well as the
Three years and $486,804.22 later, the machine made its first computation at the university. The 30-ton behemoth, and its offspring, captured the
The scientists pretty much figured things out ”they created the microprocessor, which led to the age of microcircuits ”but not until after a few scientific
Once the microprocessor hit, however, tinkerers figured how to make small computers cheap enough that everyone could afford one. Computers became personal.