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The History of Computers & Computer System
The word computer comes from a Latin word which means to “count”. Devices to assist working with numbers have been in existence as long as there have been numbers. The first was the abacus, which made use of the biquinary number system. The first mechanical computer was built by Pascal in 1642; a better device was built by Leibnitz in 1673.
The mathematician Charles Babbage made the first suggestion that a machine for mathematical computation could be built. He constructed a small working model which he demonstrated in 1822. Babbage was misunderstood by his contemporaries and died a disappointed man in 1871. After his death his son continued his work.
In the late 1940s computers were made using vacuum tubes, resistors and diodes. These computers were called the first generationcomputers.
In 1956 transistors were invented. They are made from materials called semiconductors. The computers with them were called the secondgeneration computers. Second generation computers were smaller and used less electrical power. But both the first and the second generation computers were very expensive.
In 1959 the first computer control system went on line in an industrial plant. Since then there has been remarkable advance in processing and transmitting information.
In 1960s the third generation computers were produced using integrated circuits. These circuits are made from single piece of semiconductor called a chip. With the invention of chips computer manufacture has become much simpler and less expensive.
The fundamental components of the fourth-generation computers are medium- and large-scale integration chips (MSI and LSI, respectively). An MSI chip contains between 256 and 1,000 components and an LSI chip between 1,000 and 500,000 or more components. The Fourth generation machine memories range in size up to 128 million storage locations, they function very rapidly and they utilize highly sophisticated systems and software.
The direction and features of a possible future fifth and sixth generations are not clear. Some advanced U.S. firms and the Japanese computer industry under government sponsorship have been directing their efforts in this direction since 1980s.
Computers produced nowadays can be divided into there main types, depending on their size, power and functions they perform.
Mainframe computers are the largest and the most powerful. They can handle large amounts of information very quickly and can be used by many people at the same time, usually fill a whole room. They are found at large institutions like universities and government departments.
Minicomputers commonly known as minis are smaller and less powerful than mainframes. They are about the size of an office desk and are usually found in banks and offices. They are becoming less popular as microcomputers improve.
Microcomputers commonly known as micros are the smallest and the least powerful. They are about the size of a typewriter, can handle smaller amounts of information at a time and slower than the other two types. They are ideal for use as home computers and are also used in education and business.
A computer can do very little until it is given some information. This is known as the input and usually consists of a program and some data.
Information in the form of programs and data is called software. The pieces of equipment making up the computer system are known as hardware. The most important item of hardware is the CPU (Central Processing Unit). This is the electronic unit at the centre of the computer system. It contains the processor and the main memory. The processor is the brain of the computer.
All the other devices in the computer system which can be connected to the CPU are known as peripherals. These include input devices, output devices and storage devices.
An input device is a peripheral part which enables information to be fed into the computer. The most commonly used input device is a keyboard.
An output device is a peripheral, which enables information to be brought out of the computer to display the processed data. The most commonly used output is a specially adapted television known as a monitor or VDU (Visual Display Unit). Another common output device is a printer. This prints the output of the CPU onto paper.
A storage device is a peripheral used for the permanent storage of information. It has a much greater capacity than the main memory and commonly used magnetic tape or magnetic discs as the storage medium.
Words to be remembered:
semiconductor – напівпровідник
mainframe – універсальна обчислювальна машина
to execute – виконувати, оформлювати
software – програмне забезпечення
hardware – апаратне забезпечення («залізо»)
keyboard – клавіатура
1. Match English and Ukrainian equivalents:
1. device 2. to store 3. character 4. output 5. input 6. memory 7. calculation 8. computer languages 9. processing of information 10. to perform | a. виконувати b. комп’ютерні мови c. обчислення d. обробка інформації e. символ f. введення інформації g. виведення інформації h. пристрій i. пам’ять j. зберігати інформацію |
2. Choose the correct questions to the italicized words:
1. Computers can bedifferent in size and shapes.
a. What size and shapes can computers be?
b. What do computers do?
c. What can be different in sizes and shapes?
2. A computer is a device that can use a list of instructions.
a. What is a computer?
b. What list can a computer use?
c. What can a computer do?
3. The speed and power of supercomputersare almost beyond
human comprehension?
a. What is the speed and power of supercomputers?
b. What is almost beyond human comprehension?
c. Whose speed and power are almost beyond human
comprehension?
4.More than 90 percent of the computers in use today are of this type.
a. How many computers of this type are not in use today?
b. What type of computers is in use today?
c. How many computers of this type are in use today?
5. Mainframes can perform complex mathematical operations.
a. How can mainframes perform complex mathematical
operations?
b. What can mainframes perform?
c. How can mainframes perform complex mathematical
calculation?
d. Can mainframes perform complex operations?
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