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From the first electronic digital computers of the forties to to-day's versatile computers and most up-to-date microcomputers, very little has changed as far as basic computer operation is concerned. In the last thirty years, vast improvements in the size, speed and capabilities of computers have taken place. But to-day digital computers still use the same logical operations as their predecessors. There are many basic concepts that can be applied to all types of computers, including microcomputers.

For the most part, human beings can do whatever computers can do, but computers can do it with much greater speed and accuracy, though computers perform all the calculations and operations one step at a time. A computer is faster and more accurate than people, but unlike most people it must be given a complete set of instructions that tell it exactly what to do at each step of its operation. This set of instructions, called a programme is prepared by one or more persons for each job a computer is to do. These programmes are placed in the computer's memory unit in binary-coded form, with each instruction having unique code.

Computers are often used in applications where the results of their calculations are required immediately to be used in controlling a process. These are called real-time applications; they are often found in industrial process control in industries such as paper mills, oil refineries, chemical plants, and many others. The measuring systems send their signals to the computer which processes them and responds with appropriate control signals to be sent back to the process.

Computers in present use range considerably: from tiny things to big fellows. The microcomputer, for one, is the smallest and the newest member of the computer family. It usually consists of several integrated circuit chips, including a microprocessor chip, memory chips, and input/output interface chips which are a result of tremendous advances in large-scale integration.

Minicomputers are larger than microcomputers, they are widely used in industrial control systems, scientific institutions, and research laboratories. Although more expensive than microcomputers, minicomputers continue to be widely used because they are generally faster and possess more capabilities.

The largest computers (maxicomputers) are those found in research centres, large scientific laboratories, big universities.

Most of the computer principles and concepts are common to all categories of computers, although there can be tremendous variations from computer to computer.

A question sometimes arises whether computers are able to think. As a matter of fact they do not think. The computer programmer provides a programme of instructions and data which specifies every detail of what to do, how to do, and when to do it. The computer is simply a high-speed machine which can manipulate data, solve problems, and make decisions, all under the control of the programme. If the programmer makes a mistake in the programme or puts in the wrong data, the computer will produce wrong results.

Every computer contains five essential elements or units: the arithmetic logic unit, the memory unit, the control unit, the input unit, and the output unit.

The arithmetic logic unit is the area of the computer in which arithmetic and logic operations are performed on data.

The memory unit stores groups of binary digits (words) that can represent instructions (programme) which the computer is to perform and the data that are to be operated on by the programme. The input unit consists of all the devices used to take information and data that are external to the computer and put it into the memory unit.

The output unit consists of the devices used to transfer data and information from the computer to the outside world.

The control unit directs the operation of all the other units by providing timing and control signals. This unit contains logic and timing circuits that generate the signal necessary to execute each instruction in a programme.


2. Find in the text English equivalents to the following words and word combinations:


- , , , , , , , - , , , , , , .


3. Find odd words:


mill, refinery, computer, plant;

circuit, chip, unit, program;

results, data, news, information.

4. Match the following English words with their Ukrainian equivalents. Make your own sentences with these English words.


1. digital
2. accurate
3. complete
4. appropriate
5. fast
6. expensive
7. common
8. able
9. external
10. essential


5.Put the verbs in brackets into Past Simple Tense. Translate these sentences into Ukrainian.


1. Vast improvements in the size, speed and capabilities of computers (to take place) in 1980s.

2. These programs (to be placed) in the computers memory unit in binary-coded form.

3. Charles Babbage (to design) the first computer in 1833.

4. Computers (to be found) in industrial process control in 1980s.

5. The computer programmers (to provide) a program of instructions and data.

6. Even in 1980s every computer (to contain) five essential elements or units.


6.Answer the following questions:


Where do human beings use computers?

What does the microcomputer consist of?

What is the difference between microcomputers and minicomputers?

Where are the largest computers found?

What does the computer programmer provide?

Date: 2015-01-02; view: 96

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