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# Exercises

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3.1. Present in written form and learn by heart the four forms of the following verbs. Make sure that you know their meaning.

leave; remain; retain; build; lie; lay; lead.

3.2. Give examples from the text of the verbs in the Perfect tense forms and the gerunds.

3.3. Find in the text the English for:

до нашей эры, будучи опытными, укрепление, согласно, так называемый, до сегодняшнего дня, состоять из, быть окруженным чем-либо.

3.4. Write the cardinal and ordinal numerals into English:

55; 4; 17; 23; 82; 100; 2005; 1981; 798.

Unit 4

HISTORY OF COMPUTERS

When you read the following text, you will probably meet words and expressions that are new to you. First try to understand their meaning from the context – read the same passage a few times. When you have read the whole text, check new words in a dictionary.

Let us take a look at the history of the computers that we know today. The very first calculating device used was the ten fingers of a man’s hands. This, in fact, is why today we still count in tens and multiples of tens then the abacus was invented, a bead frame in which the beads are moved from left to right. People went on using some forms of abacus well into the 16th century, and it is still being used in some parts of the world because it can be understood without knowing how to read.

During the 17th and 18th centuries many people tried to find easy ways of calculating. J. Napier, a Scotsman, devised a mechanical way of multiplying and dividing, which is how the modern slide rule works. Henry Briggs used Napier's ideas to produce logarithm tables which all mathematicians use today. Calculus, another branch of mathematics, was independently invented by both Sir Isaac Newton, an Englishman, and Leibniz, a German mathematician.

The first real calculating machine appeared in 1820 as the result of several people's experiments. This type of machine, which saves a great deal of time and reduces the possibility of making mistakes, depends on a series of ten-toothed gear wheels. In 1830 Charles Babbage, an Englishman, designed a machine that was called 'The Analytical Engine. This machine, which Babbage showed at the Paris Exhibition 20 in 1855, was an attempt to cut out the human being altogether, expect for providing the machine with the necessary facts about the problem to be solved. He never finished this work, but many of his ideas were the basis for building today’s computers.

In 1930, the first analog computer was built by an American named Vannevar Bush. This device was used in Word War II to help aim guns. Mark I, the name given to the first digital computer, was completed in 1944. The men responsible for this invention were Professor Howard Aiken and some people from IBM. This was the first machine that could figure out long lists of mathematical problems, all at 30 a very fast rate. In 1946 two engineers at the University of Pennsylvania, J. Eckert and J. Mauchly, built the first digital computer using parts called vacuum tubes. they named their new invention ENIAC. Another important advancement in computers came in 1947, when John von Newmann developed the idea of keeping instructions for 35 the computer inside the computer's memory.

The first generation of computers, which used vacuum tubes came out 1n 1950. Univac I is an example of these computers which could perform thousands of calculations per second. In 1960, the second generation of computers was developed and these could perform work 40 ten times faster than their predecessors. The reason for this extra speed was the use of transistors instead of vacuum tubes. Second –generation computers were smaller, faster and more dependable than first-generation computers. The third-generation computers appeared on the market in 1965. These computers could do a million calculations 45 a second, which 1000 times as many as first-generation computers. Unlike second-generation computers, these are controlled by tiny integrated circuits and are consequently smaller and more dependable. Forth-generation computers have now arrived, and the integrated circuits that are being developed have been greatly reduced in size. This 50 is due to microminiaturization, which means that the circuits are much smaller than before; as many as 1000 tiny circuits now fit onto a single сhip. A chip as a square or rectangular piece of silicon, usually from 1/10 to 1/4 inch, upon which several layers of an integrated circuit are etched or imprinted, after which the circuit is encapsulated in plastic, ceramic 55 or metal. Fourth-generation computers are 50 times faster than third generation computers and can complete approximately 1,000,000 instructions per second.

At the rate computer technology is growing, today's computers might be obsolete by 1988 and most certainly by 1990. It has been said that if 60 transport technology had developed as rapidly as computer technology, a trip across the Atlantic Ocean today would take a few seconds.

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