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The Early History of Computers

People have been "computing" throughout history, probably since they first learned how to count with pebbles. People living in the ancient civilization of the Tigris-Euphrates Valley about 5000 years ago used a fire-hardened clay board with grooves in which pebbles could be moved easily from one side to the other. The abacus – which uses movable beads strung on wires above and below a crossbar – is thought to have originated in China about 2600 B.C.

Pascal

In 1642 Blaise Pascal (1623 – 1662) invented an automatic desktop machine that could add and subtract. Pascal's calculator consisted of a set of toothed wheels, or gears. Each wheel had the numbers 0 through 9 engraved on it, one number for each tooth of the wheel. The user could add or subtract by turning the wheels.

Pascal’s counting machine still had a few drawbacks: it could only add and subtract, not multiply and divide, and the results were not always accurate because the gears often got stuck between two digit positions.

Leibniz

In 1671 the German philosopher Gottfried Wilhelm von Leibniz (1646-1716) developed the “stepped reckoner”. This device could also multiply and divide by using repeated additions and subtractions. Although many models of Leibniz's machine were used in his day, his later designs for improved calculating devices could not be produced commercially: precision machine tooling to make identical metal parts did not exist in the 17th century.

Babbage

Charles Babbage (1791-1871), professor of mathematics at Cambridge University, became annoyed by the mathematical errors he was constantly finding in printed navigational and astronomical tables. He hit on the idea that those tables might be more accurately calculated by machines. The "difference engine," which he invented in 1822, was designed to compute polynomials. Babbage next went to work on an "analytical engine." A dramatic improvement over his one task computer; the analytical engine was a kind of general-purpose computer designed to solve any arithmetic problem. It had most of the elements present in today's digital computer systems: a "mill," or processing unit, which manipulated data; a «store», or memory, which held information; data recorded on punched cards, or input; and automatic printing of computations, or output. A logical set of instructions led the user to subdivide calculations into steps performed in a sequence – in other words, a program. Babbage's analytical engine was very complicated and required thousands of gears, levers, and belts all working together in fine-tuned precision. Although he worked on it obsessively until his death in 1871, Babbage never completed his wonderfuI machine.

Lady Ada Augusta Lovelace

Lady Ada Augusta Lovelace (1815-1852), daughter of the poet Lord Byron, was an admirer of Babbage and his work. Lady Ada has been called the first programmer. She figured out that the same set of punched cards could be reused to repeat certain instructions. Today we call these instructions in a program "loops" and "subroutines."

Hollerith and the American Census

Dr. Herman Hollerith (1860-1929), a mechanical engineer and statistician, suggested the use of punched cards to record census data. His cards had 288 locations where holes could be punched. The rows and columns of holes in Hollerith's punched cards represented numerals and population characteristics. To handle these cards, Hollerith built an electric machine that could tabulate them at the rate of 50 to 75 a minute. The machine contained metal pins that "read" each of the 288 locations in each card. Wherever holes had been punched a pin would pass through the card, making contact with mercury-filled cups and completing an electric circuit. Each time a circuit was closed, a counting mechanism in the machine was activated. In this way the different items contained on the cards were tabulated at the same time. In 1896 Hollerith set up the Tabulating Machine Company, which manufactured both the machines and the cards. After many mergers and name changes, Hollerith's company eventually became part of IBM.

George Boole

George Boole (1815 – 1864), had introduced a theory of logic, in what is now known as Boolean algebra. Boole reduced logic to two-valued binary notation. In binary notation, only the values 1 and 0 are used to express numbers.Binary notation turned out to be virtually made to order for electronic components, which can be either on (the equivalent of 1) or off (the equivalent of 0). All these inventions paved the way for the birth of the electronic digital computer.

The Mark I

In 1937 Howard H. Aiken started developing a computer at Harvard University. Aiken wanted to combine a punched-card input method with contemporary electrical and mechanical technology. In 1944 Aiken and four IBM engineers completed the Mark I.

The Mark I was 50 feet long and 8 feet high. Its thousands of moving parts were controlled by electric current. It took Mark I approximately 4 1/2 seconds to multiply two 23-digit numbers. The Mark I fed raw data on punched paper tape into a "mill," where the calculations, supervised by a set of logical instructions, were performed.

The Atanasoff-Berry Computer

Dr. John V. Atanasoff, a physicist at Iowa State College, made an important contribution to the continuing development of computers. In 1939, Atanasoff, assisted by a graduate student named Clifford Berry, built the first electronic digital computer, called the ABC or Atanasoff-Berry Computer. Atanasoff's machine was the first entirely electronic computer, using vacuum tubes rather than electromechanical relays. The vacuum tubes functioned as switches and were able to close circuits much more rapidly than electromechanical parts which meant that calculations could be done faster.

ENIAC

The Electronic Numerical Integrator and Computer (ENIAC) was developed by John W. Mauchly and John Presper Eckert, Jr., at the University of Pennsylvania. Mauchly and Eckert had already been discussing the feasibility of developing an electronic computer when the U.S. Army's Ballistic Research laboratories came to them with the problem of computing new- trajectory tables for use in World War II. The electronic-computer project got under way in April 1943. In 1946, ENIAC was finished, too late to contribute to the war effort, but in plenty of time to set new records for calculating speed. The ENIAC could do an unprecedented 5000 additions per second. In half a minute it could solve a problem that usually took the desktop adding machines of that day 20 hours. As you can see, the greatest asset of modern computers – their speed – was first experienced with ENIAC. The new computer had its limits, however. It contained more than 18,000 vacuum tubes; it needed a huge amount of electric power to run. It could store only 20 numbers of 10 digits each. Its operations were controlled by programs that required manual rewiring. In fact, a program change meant rewiring some 40 interconnected control panels, which took days.
ENIAC's calculating speed was offset to some extent when the time lost in rewiring the machine was taken into account.

The Stored-Program Concept

Hungarian-born mathematician John von Neumann found the solution to this problem: the stored program. With a stored program, the instructions for the computer are coded as numbers and stored inside the machine. The machine's operating instructions are placed, or stored, in the same memory as the data to be processed, and they are written in the same binary notation. The basic operations that the machine can perform are built into its circuitry; each operation is given a number; and the stored program can call for any operation by its number.

Notes:

1. 
   … a fire hardened clay board with grooves — дощечка из обожженной глины с желобками
   
2. 
   The abacus … is thought to have originated in China about 2600 B.C. — Полагают, что счеты появились в Китае около 2600 года до н.э.
   
3. 
   a set of toothed wheels, or gears — ряд зубчатых колесиков или шестеренок
   
4. 
   stepped reckoner — пошаговое счетное устройство
   
5. 
   He hit on the idea — ему пришла идея
   
6. 
   census data — данные переписи населения
   
7. 
   Whenever holes had been punched a pin would pass through the card, making contact with mercury-filled cups — Где бы ни пробивались отверстия, игла проходила сквозь перфокарту, соприкасаясь с чашами, наполненными ртутью
   
8. 
   to some extent — до некоторой степени
   
9. 
   IBM — International Business Machines Corporation (Aмериканская компания по разработке и производству аппаратного и программного обеспечения)
   

I . Answer the following questions:

1.What instrument was invented for counting before a mechanical way for multiplying and dividing appeared ? 2. Who invented the analytical engine ? 3. When were punched cards first used ? 4. What parts did Pascal’s calculator consist of ? 5. Were there any drawbacks in Pascal’s machine ? 6. What could the “stepped reckoner” do ? 7. Who is considered to be the first programmer ? 8. In what way did Hollerith’s electric machine tabulate punched cards ? 9. What inventions paved the way for the birth of the electronic digital computer ? 10. Who is credited with the development of the stored program concept ?

II . Give the main ideas of the text in logical order.

III . Translate in writing: