Second Generation Computers (1956-1963)

By 1948, the invention of the transistor greatly changed the compu­ter's development. The transistor replaced the large, cumbersome vacu­um tube in televisions, radios and computers. As a result, the size of electronic machinery has been shrinking ever since. The transistor was at work in the computer by 1956. Coupled with early advances in magnet­ic-core memory, transistors led to second generation computers that were smaller, faster, more reliable and more energy-efficient than their prede­cessors. The first large-scale machines to take advantage of this transis­tor technology were early supercomputers, Stretch by IBM and LARC by Sperry-Rand. These computers, both developed for atomic energy laboratories, could handle an enormous amount of data, a capability much in demand by atomic scientists. The machines were costly, howev­er, and tended to be too powerful for the business sector's computing needs, thereby limiting their attractiveness. Only two LARCs were ever installed: one in the Lawrence Radiation Labs in Livermore, California, for which the computer was named (Livermore Atomic Research Com­puter) and the other at the U.S. Navy Research and Development Cent­er in Washington, D.C Second generation computers replaced machine language with assembly language, allowing abbreviated programming codes to replace long, difficult binary codes.

Throughout the early 1960's, there were a number of commercially successful second generation computers used in business, universities, and government from companies such as Burroughs, Control Data, Honeywell, IBM, Sperry-Rand, and others. These second generations

computers were also of solid state design, and contained transistors in place of vacuum tubes. They also contained all the components we asso­ciate with the modern day computer: printers, tape storage, disk storage, memory, operating systems, and stored programs. One important ex­ample was the IBM 1401, which was universally accepted throughout industry, and is considered by many to be the Model T of the computer industry. By 1965, most large business routinely processed financial in­formation using second generation computers.

It was the stored program and programming language that gave com­puters the flexibility to finally be cost effective and productive for busi­ness use. The stored program concept meant that instructions to run a computer for a specific function (known as a program) were held inside the computer's memory, and could quickly be replaced by a different set of instructions for a different function. A computer could print custom­er invoices and minutes later design products or calculate paychecks. More sophisticated high-level languages such as COBOL (Common Business-Oriented Language) and FORTRAN (Formula Translator) came into common use during this time, and have expanded to the cur­rent day. These languages replaced cryptic binary machine code with words, sentences, and mathematical formulas, making it much easier to program a computer. New types of careers (programmer, analyst, and computer systems expert) and the entire software industry began with second generation computers.

 

Ответьте на вопросы к тексту:

1. Who succeeded in producing an all-electronic calculater?

2. What was the main advantage of the Electronic Numerical Integrator and Computer?

3. When did the Electronic Discrete Variable Automatic Computer design?

4.Did the invention of the transistor change the computer`s development?

5. Why were second generation computers used successfully in business in 1960`s?

6. What languages did replace cryptic binary machine code?

7. What types of careers did appear with second generation computers?

Текст 2

Development of Computers

In the 19th century the need for rapid calculation expanded through­out the industrial world. Governments taxed and policed larger popula­tions than ever before. Commerce expanded so that there were more money transactions than ever before.

Armies of clerks were employed to calculate and record the mass of transactions conducted by business houses, banks and insurance compa­nies. Scientists and engineers required ever more extensive tables of figures.

To meet the demand, new designs of calculating machine were devised.

In the 20th century electricity was harnessed to drive a variety of calculating machines. But the first general-purpose computing machine that was fully electronic was ENIAC (Electronic Numeral Integrator and Calculator), completed at the University of Pennsylvania in 1945. It employed more than 18, 000 thermionic valves, weighed 30 tons and oc­cupied 1, 500 sq. ft of floor space.

In the post-war years more computers were built, generally in uni­versity research departments. The term 'electronic brain' was coined.

The first part of the economy in which computers became important was finance. In banks and finance houses information began to be re­corded directly in machine-readable form by operators at keyboard machines. At first numbers were recorded on punched paper tape or cards; later these were supplanted by magnetic tape and discs. The num­bers of clerical staff did not fall, but their productivity rose as the number of transactions they could process swelled. In the early 1980s, for in­stance, in Britain the National Westminster Bank processes some 2 mil­lion cheques and 650, 000 credits in each working day.

Large companies computerised their payrolls. Shops and stores kept track of goods with the aid of computers and cut their reserve stocks; hence they could reduce their warehouse costs and free space for a wider variety of goods.

Complex industrial processes such as oil refining and steel-rolling were handed over to the control of the computer. Industrial design de­pended more and more on the computer. It would be impossible to de­sign a new car or jet airliner with a reasonable expenditure of time and money without computers to carry out the enormous number of calcula-tions involved.

The mammoth American company IBM dominated these develop­ments. When delivery of Univac II, announced by IBM's rival Reming­ton Rand in 1955, was delayed until 1957 by production difficulties, IBM captured the market in large computers.

IBM maintained its lead when the 'second generation' of computers appeared around 1960. These employed transistors in place of valves and were more powerful than their predecessors, yet more compact, re­liable and economical of energy. They could be housed in a few cabinets, rather than filling a large air-conditioned room.

The trend towards smallness and cheapness was enormously accel­erated when the 'third generation' of computers, based on the silicon chip, appeared around 1965. Electronic components, such as transistors, could now be made in large numbers on a thin square of silicon, typically 1/4 in. square. By 1971 the first microprocessor had appeared in Ameri­ca: the microprocessor was the heart of a computer - the part that does l lie actual calculating - on a single chip. Other chips could provide mem­ory stores.

When input/output devices, such as a keyboard and printing ma­chine, were added, a complete computing system was obtained that could lit on to a desktop. Such a unit can store about 2 1/2 million characters -letters or numbers - of information. Calculations are completed in sec­onds and the print-out is between 80-120 characters a second.

A visual display unit - a TV screen that could display text punched in by means of a keyboard, together with the computer's replies - per­mitted an operator to put instructions and questions to the computer and receive responses.

The computer, now smaller, cheaper and more accessible to ordi­nary people than ever before, has appeared in the office, on the factory floor and in the home. Computer terminals are seen at airline and theatre reservations desks, in stockbrokers' offices, in factory stockrooms, in power-station control rooms and in banks.

Even the toy departments in large stores sell computers: some create video games on home TV sets; others play chess and draughts - some­times with the machine speaking its moves. But the increasing power of the computer and its 'software' - its programming - has transformed daily life in ways that can pass unnoticed. Computer-fed weather fore­casts are more accurate and range further ahead. Greater volumes of road traffic are handled with less delay, by computerized traffic-light systems responding to information about the flow of vehicles from automatic sensors.

Some cars are now equipped with a microcomputer that continuously controls the fuel mixture and ignition timing, which optimizes performance and economises on fuel. There are also trip computers which display details of average speed and fuel consumptions since the beginning of the journey.

 

Ответьте на вопросы к тексту:

1. What century was electricity harnessed to drive a variety of calculating machine?

2. What was the first part of the economy in which computers became important?

3. When did appear the first microprocessor?

4. In what fields of industry are computers used?

5. What is role of microcomputer in modern cars?

Текст 3

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