Study this chart and make sentences about Alice and you.

Example 1: a) Alice attended classes in programming the day before yesterday.

b) I …

When did you …?	Alice	You
1. go to the library	two weeks ago	?
2. attend classes in programming	the day before yesterday	?
3. use the Internet	yesterday	?
4. work at the Internet centre	last week	?

Example 2: a) Alice didn’t study a programming language yesterday.

b) I …

What did/didn’t you do yesterday?	Alice	You
1. test computer programs	+	?
2. study a programming language	-	?
3. play computer games	+	?
4. work on a computer	+	?

7. Answer your partner’s questions.

Example: to print information on paper

-Did you print information on paper yesterday?

-Yes, I did. I printed information on paper yesterday.

1) to work at the computer centre

2) to solve tasks on higher mathematics

3) to study the history of computer development

4) to discuss the problems of biochip circuitry at the lessons

5) to write a course paper on a computer

Read the text quickly and arrange the items of the given outline in the order according to the text.

1) Ch. Babbage’s contribution to the automatic computer development.

2) The abacus, the oldest form of mechanical calculating devices.

3) Calculating devices of the 17th century.

4) Thе first electronic computer (ЕNIAC).

5) The first completely automatic digital computer.

From the History of Computer Development

Part I

The oldest form of mechanical calculating devices was the abacus¹. It remained the only аid to calculation until the 17th century. After the invention of logarithms in 1614, W. Oughtred constructed the first slide-rule in 1630. B. Pascal built an adding machine in 1642 at the age of 19. Later he produced some others, one of them could add six-figure numbers. In 1671 Leibnitz invented the first machine, which performed multiplication by repeated addition.

Ch. Babbage, the English mathematician of the 19th century, was the first who conceived the idea of the automatic machine for complex calculations. He designed his Analytical Engine to perform four arithmetic operations. Ch. Babbage couldn’t translate his ideas into reality because there were no reliable and accurate electrical equipment, but his Analytical Engine was a true prototype of the modern digital computer. Ch. Babbage and Lady Lovelace, Lord Byron’s daughter, worked out a coded program. Lady Lovelace was a brilliant mathematician. She believed and fully understood the potentialities of the Analytical Engine. She took an active part in Babbage’s experiments. So it is fair to say that she was the world’s first computer programmer.

About seventy years passed before the production of the first digital computer, which was similar to Babbage’s Analytical Engine. In 1937 Dr. H. Aiken of Harvard University began to work at the first completely automatic digital computer which he called the Mark 1. He completed it in 1944. The Mark 1 was mainly mechanical with some electro-magnetic devices. It was a very large computer, 51 feet long and 8 feet tall. The store had 72 counters. Each counter could hold 23 digits.

The first electronic computer, the Electronic Numerical Integrator and Calculator (ENIAC), was constructed in 1946 at the University of Pennsylvania. The machine used 18,000 vacuum tubes⁵ for storage and basic functions in arithmetic and logic. Though it was not as large as the Mark 1, it weighed 30 tons and measured 20 by 40 feet. Whereas the Mark 1 could add 2 numbers in one-third of a second, ENIAC could add 5000 numbers in one second.

In 1945 John von Neuman worked out the concept of the stored program. He recommended to store operational instructions and numbers in the same unit in the binary system. EDVAC, EDSAC, UNIVAC were the first computers which put these new ideas into practice.

Notes

¹an abacus – абак, счеты

²a mill – зд. решающее устройство

³a sequence mechanism – устройство, определяющее порядок работы

⁴would call – назвали бы

⁵a vacuum tube – электронная лампа

Дата добавления: 2015-07-21