Taking Сomputer for Granted. Учебное пособие
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work on a new machine. The main contribution of their new project, was the notion of stored program. There is some controversy over who deserves the credit for this idea, but none over how important the idea was to the future of general purpose computers. Through the use of a memory that was large enough to hold both instructions and data, and using the program stored in memory to control the order of arithmetic operations, this machine was able to run orders of magnitude faster than it was done before. By storing instructions in the same medium as data, designers could concentrate on improving the internal structure of the computer without worrying about matching it to the speed of an external control.
By recognizing that functions, in the form of a sequence of instructions for a computer, can be encoded as numbers, the scientists realized the instructions could be stored in the computer’s memory along with numerical data.
Software technology during this period was very primitive. The first programs were written out in the machine code, i.e. programmers directly wrote down the numbers that corresponded to the instructions they wanted to store in memory. By the 1950s programmers were using a symbolic notation, known as assembly language, than hand-translating the symbolic notation into machine code. Later programs known as assemblers performed the translation task.
As primitive as they were, these first electronic machines were quite useful in applied science and engineering. One of the scientists estimated that it would take eight hours to solve a set of equations with eight unknowns using a previous calculator, and 381 hours to solve 29 equations for 29 unknowns. The up to time computer was able to complete the task in under an hour. The first problem run on it, a numerical simulation used in the design of the hydrogen bomb, required 20 seconds, as opposed to forty hours
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using mechanical calculators. Later the first commercially successful computer was developed. In 1952, 45 minutes after the polls closed and with 7% of the vote counted, it predicted Eisenhower would defeat Stevenson with 438 electoral votes (he ended up with 442).
Second generation (1954-1962)
The second generation saw several important developments at all levels of computer system design, from the technology used to build the basic circuits to the programming languages used to write scientific applications.
Electronic switches in this era were based on discrete diode and transistor technology with a switching time of approximately 0.3 microseconds. The first machines were built with this technology at Belland Lincoln Laboratories. Memory technology was based on magnetic cores which could be accessed in random order as opposed to the previous devices.
During this second generation many high level programming languages were introduced, including FORTRAN (1956), ALGOL (1958), and COBOL (1959). Important commercial machines of this era include the IBM 704 and its successors, the 709 and 70094.
The second generation also saw the first supercomputers designed specifically for numeric processing in scientific application. The term «supercomputer» is generally reserved for a machine that is an order of magnitude more powerful than other machines of this era.
Third generation (1963-1972)
The third generation brought huge gains in computational power. Innovations in this era include the use of integrated circuits, or ICs (semiconductor devices with several transistors built into one physical component), semiconductor memories starting to
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be used instead of magnetic cores, microprogramming as a technique for efficiently designing complex processors, the coming age of parallel processing, and the introduction of operating system.
The first ICs were based on small-scale integration (SSI) circuits, which had around 10 devices per circuit (or «chip»), and evolved to the use of circuits, which had up to 100 devices per chip. Multilayered printed circuits were developed and core memory was replaced by faster, solid state memory. Computer designers began to take advantage of parallelism by using multiple function units. In 1964, Seymour Cray developed the CDC 6600, which was able to attain a computation rate of 1 million floating point operations per second (1 Mflops). Five years later the CDC 7600 was capable of executing at 10 Mflops. At the same time IBM and other companies released computers of about the same rate of operations.
During this period Cambridge and the University of London cooperated in the development of CPL (Combined Programming Language, 1963). CPL was an attempt to simplify the complicated and sophisticated ALGOL, but this program was still hard to learn; therefore it was followed by BCPL (Basic Computer Programming Language, 1967). Later (1970) in Bell Labs another simplification of CPL was developed and called «B».
The incredibly fast progress in hardware, software and its technologies has begun.
Computer speech
Think twice before you speak to a friend in need.
A. Bierce
Compression It is often possible to remove redundant information or to process it in lesser amount of storage space. Usually when a file has been compressed, it cannot be used until it is uncompressed.
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Embedded An embedded system is a computer that is inside another device and acts as a component of that device. E.g. cars have an embedded computer that helps regulate their day to day operations.
Extension Filename extensions allow a rough grouping of different file types by putting a tag at the end of the name.
Partition Sometimes due to hardware limitations, discs have to be divided into smaller pieces. These pieces are called partitions.
Protocol is a means of communication used between computers. If both computers recognize the same protocol, they can communicate over the same network or even via a simple direct modem connection regardless whether or not they are themselves of the same type.
UPS Abbreviation for an uninterrupted power supply. It includes heavy duty batteries to help smooth out its input power source.
2.Exercises
1.Read and translate the text.
2.Check up your understanding. Give full answers:
1.Looking back, when do you think the history of computers began?
2.How do you understand the term «computer generation»?
3.What do you know about the first programmable computing device?
4.Who constructed the first machine?
5.What was it used for?
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6.Why the first period of the computer history is called «The mechanical era»?
7.What do you know about the first generation of electronic computers?
8.What do you know about the first electronic computer?
9.What was Colossus? What task it performed?
10.What do you think about software technology developed for the first generation electronic computers?
11.Were the computers of the first generation useful? Why?
12.How long lasted the period of the first computer generation? What was the first and the last event?
13.Why do you think computers were invented? What was the purpose?
3.Retell the text briefly using the following expressions and terms:
Can be traced, as far as, programmable computing device, electronic calculator, break codes, through the use of, hold instructions and data, assembly language (assembler), to run orders of magnitude, arithmetic operations, machine code, up to time computer, weather prediction, computer design, scientific applications, high level programming languages, memory technology, computational power, IC, CPL.
4.What’s missing? If you are in doubt refer to the text.
1.During the early days of electronic computing devices, there was much discussions …. the relative merits of analog versus digital computers.
2.…. the end digital computing devices proved to have many advantages.
3.Now digital computers dominate the computing world …. in all areas.
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4.The 1st and the 2nd units are limited …. the area …. digital, electronic computers.
5.Each generation is characterized …. improvements …. the previous generation …. technology.
6.Their machine won a gold medal …. the exhibition …. France …. 1855.
7.Later this machine was sold …. one …. the of observatories
….the US.
8.The first electronic computers had no moving parts that would wear …. .
9.Colossus played an important role …. breaking codes used
….the German army …. the World War II.
10.Turing machine was used …. the study …. computable functions.
11.The credit due …. Turing and his colleagues …. designing one of the first computers was slaw …. coming.
12.There is some controversy …. who deserves the credit …. the idea …. a stored program.
13.Computers are very useful … applied science.
14.Computer technology …. the first generation period was primitive.
5.Rearrange the words and get the right sentences:
1.was never / multi-purpose / device / the first / completed / computing/.
2.was / calculator / of / an /electronic / the machine / more /.
3.this idea / knows / who / the credit / for / nobody / deserves /.
4.are stored / as / the same / the instructions / medium / in/ data /.
5.generation / saw / the first / the second / super computers/.
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6.enough / to hold / was / the instructions / and / large / data / the memory /.
7.in / were / useful / machines / applied / the first / electronic / science /.
8.the machine / were written / in / the first / code / out / programs /.
9.primitive / the beginning / very / technology / was in / software /.
10.as / performed / known / programs / the / translation / assemblers / task /.
6.Put the letters in order to make words, then use the words to complete the sentences:
guicopmtn, raalccculto, somcprute, getchnoloy, ncbtontriuio, amgtdniue, mmdeiu, owls
1.Digital computers now dominate the …. world in all areas ranging from the hand …. to the supercomputer.
2.The mechanical era of …. lasted from 1623 up to 1945.
3.The main reason Babbage was not able to complete his projects was the fact that the …. of the day was not reliable.
4.Turing’s main …. to the field of computer science was the idea of the Turing machine.
5.Through the use of a memory EDVAC was able to run orders of …. faster than ENIAC.
6.The designers stored instructions and data in the same …. .
7.The first computers were extremely ….. .
7.There are two words in each item. You must explain how is «a» like «b» and how «a» differs from «b»:
1.(a) work, (b) job;
2.(a) difference, (b) likeness;
3.(a) competitor (b) opponent;
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4.(a) mechanical computer, (b) electronic computer;
5.(a) gold, (b) silver;
6.(a) construct, (b) design;
7.(a) computer, (b) calculator;
8.(a) purpose (b) goal;
9.(a) fast (b) slow;
10.(a) complex (b) primitive.
8.Give the opposites of the following words:
1. early; 2. digital; 3. arise; 4. supercomputer; 5. evolution; 6. science; 7. wide; 8. be capable; 9. reliable; 10. merge; 11. complete; 12. win; 13. open; 14.finish; 15. external; 16. faster;
17.large; 18. modern; 19. be able; 20. powerful.
9.Give the synonyms of the following words:
1. evolution; 2. machine; 3. construct; 4. major; 5. need; 6. general;
7.found; 8. complete; 9. improve; 10. concentrate; 11. match.
10.What verbs precede these words?
1.improvement; 2. a machine; 3. technology; 4. a calculator;
5.benefit; 6. a role; 7. codes; 8. a task; 9. a problem; 10. a circuit.
11.Supply the articles where necessary:
1.…. first programmable computing device was begun in 1823.
2.…. evolution of computers technique is divided into generations.
3.Their machine won …. gold medal at …. Exhibition in Paris, and later it was used to calculate …. orbit of Mars.
4.…. engineers began to work on …. smaller version.
5.One of …. first commercial uses of mechanical computers was by …. US Census Bureau.
6.…. technology was still new at that time and …. tubes were comparable to relays in reliability.
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7.…. earliest attempt to build an electronic computer was realized in 1937.
8.…. second early electronic machine was Colossus, designed for the British military in 1943.
9.….Turing’s main contribution to …. field of computer science was …. idea of …. Turing machine, …. mathematical formalism widely used in …. study of computable functions.
10.…. main contribution of their new project, was …. notion of stored program.
12.Translate into English:
1.Спор о преимуществах цифровых компьютеров по срав- нению с аналоговыми продолжался длительное время до
1960 года.
2.Все цифровые компьютеры в зависимости от их возможно- стейиконструкцииразделяютнанесколькопоколений.
3.Каждое поколение превосходит по своим характеристи- кам предыдущее.
4.Поэтому, фактически, история развития компьютеров является историей развития их поколений.
5.Самая первая компьютерная эра, которая была самой длительной, связана с развитием механических компью- теров.
6.Первый компьютер, получивший золотую медаль на вы- ставке в Париже, был разработан в 1893 году.
7.Первая компьютерная корпорация была создана в 1911 году, когда слились две конкурирующие компьютерные компании.
8.Самая первая попытка построить электронный компью- тер была предпринята в 1941 году.
9.Этот компьютер сыграл важную роль во время второй мировой войны, так как был использован для дешиф- ровки немецких секретных кодов.
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10.Создание памяти было важным шагом в истории разви- тия современных компьютеров.
11.В современных компьютерах память можно наращивать (увеличивать).
13.Are you up to giving a right explanation?
Look for a statement in this book or put your own idea in an oral frame and use it.
DO and MAKE
Many times you have come across these two verbs.
Maybe you even know that they are not interchangeable. If so, check yourself.
Complete the following sentences with do or make.
1.You must …. your duty.
2.Do not …. fun of me. I don’t like it.
3.A glass of whisky will …. you good.
4.Do not try to …. me out a liar.
5.Thank you, you have …. a lot of business with us.
6.You …. a big mistake getting in touch with this company.
7.She’ll …. him a good wife.
8.I’m …. a speech tomorrow.
9.After hot discussions they …. peace at last.
10.I …. my homework yesterday.
11.It won’t …. you any harm to …. this exercise again.
If you’re in doubt we can help you.
DO and MAKE have different meanings. Do means to perform routine work.
Make means to create. Hence, we say, for example, «I did my homework yesterday». Here you use «do» because you had been taught how to fulfill this work. But you say «I made mistake» because it’s your own fancy.
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