HISTORY OF COMPUTERS

HISTORY OF COMPUTERS

The history of computing began with an analog machine. In 1623 German scientist Wilhelm Schikard invented a machine that used 11 complete and 6 incomplete sprocketed wheels that could add, and with the aid of logarithm tables, multiply and divide.

French philosopher, mathematician, and physicist Blaise Pascal invented a machine in 1642 that added and subtracted, automatically carrying and borrowing digits from column to column. Pascal built 50 copies of his machine, but most served as curiosities in parlors of the wealthy. Seventeenth-century German mathematician Gottfried Leibniz designed a special gearing system to enable multiplication on Pascal’s machine.

Abacus, instrument used in performing arithmetic calculations. The abacus is an instrument used to perform arithmetic calculations. A mechanical device for making calculations consisting of a frame mounted with rods along which beads or balls are moved.  Developed in ancient times, the abacus is still used in China, Japan, and Korea.  It consists essentially of a tablet or frame bearing parallel wires or grooves on which counters or beads are moved. A modern abacus consists of a wooden frame with beads on parallel wires, and a crossbar oriented perpendicular to the wires that divides the beads into two groups. Each column—that is, each wire—represents one place in the decimal system. The column farthest to the right is the ones column; the next column to the left is the tens column; and so on. In each column, there are five beads below the crossbar, each of which represent one unit, and two beads above the crossbar, each of which represent five units. For example, in the tens column, each of the group of five beads represents ten, and each of the group of two beads represents fifty. Beads that are to be counted as part of a number are placed against the crossbar. Many early civilizations used the abacus. In ancient Roman culture it was a sand-covered wax tablet, marked table, or grooved table or tablet. A simplified form of abacus was used in medieval England. It consisted of a tablet ruled into spaces representing the positions of the counters; coins, buttons, stones, or other small objects were moved to make the calculations. The checkered tablecloth, from which the name Exchequer is derived, was originally a calculating device like the ruled tablet. The abacus is still used in China and Japan.

The Pascaline Machine/Leibnitz

Adding Machine, mechanical device for adding (and usually subtracting, multiplying, and dividing) numbers. Early versions of this calculator appeared in the 17th century and operated with gears and wheels. In the 20th century, electrical power increased speed and efficiency until the 1960s and 1970s, when electronic calculators, embedded with computer chips, began replacing adding machines.

Gottfried Wilhelm Leibniz, also Leibnitz, Baron Gottfried Wilhelm von (1646-1716), German philosopher, mathematician, and statesman, regarded as one of the supreme intellects of the 17th century.

The Babbage Machine:  Analytical Engine, a mechanical calculating machine that was conceived by British mathematician and scientist Charles Babbage in 1833 but only a part of which was ever constructed. The first general-purpose digital computer, the Analytical Engine, although conceived long before electronics technology appeared, was to have been capable of storing instructions, performing mathematical operations, and using punched cards as a form of permanent memory.  Charles Babbage invented the Difference Engine, a mechanical device designed to handle complicated mathematical problems.  The Analytical Engine, an archetype of the modern digital computer. The technology of their time was not capable of translating their ideas into practical use, but the Analytical Engine had many features of the modern computer. It could read data from a deck of punched cards, store data, and perform arithmetic operations.  Charles Babbage (1792-1871), British mathematician and inventor, who designed and built mechanical computing machines on principles that anticipated the modern electronic computer. Babbage was born in Teignmouth, Devonshire, and was educated at the University of Cambridge. He became a fellow of the Royal Society in 1816 and was active in the founding of the Analytical, the Royal Astronomical, and the Statistical societies. 

In the 1820s Babbage began developing his Difference Engine, a mechanical device that can perform simple mathematical calculations. Babbage started to build his Difference Engine, but was unable to complete it because of a lack of funding. However, in 1791 British scientists, following Babbage's detailed drawings and specifications, constructed the Difference Engine. The machine works flawlessly, calculating up to a precision of 31 digits, proving that Babbage's design was sound. In the 1830s Babbage began developing his Analytical Engine, which was designed to carry out more complicated calculations, but this device was never built. Babbage's book Economy of Machines and Manufactures (1832) initiated the field of study known today as operational research.

Considered by many to be a direct forerunner of the modern computer, the Difference Engine was able to compute mathematical tables. This woodcut shows a small portion of the ingenious machine, which was designed by Charles Babbage in the 1820s. Although the device did not have a memory, Babbage’s later idea for the Analytical Engine would have been a true, programmable computer if the technology of his time had been able to build it.

Difference Engine, an early computer like mechanical device designed by British mathematician and scientist Charles Babbage in the early 1820s. Although never completed by Babbage, the Difference Engine was intended to be a machine with a 20-decimal capacity capable of solving mathematical problems. The concept of the Difference Engine was enhanced by Babbage in the 1830s in the design of his more famous Analytical Engine, a mechanical precursor of the electronic computer. Babbage, incidentally, was also the inventor of the speedometer and the cowcatcher.

The Hollerith Machine:  Herman Hollerith (1860-1929), American inventor, born in Buffalo, New York, and educated at Columbia University, who devised a system of encoding data on cards through a series of punched holes. This system proved useful in statistical work and was important in the development of the digital computer. Hollerith's machine, used in the 1890 U.S. census, “read” the cards by passing them through electrical contacts. Closed circuits, which indicated hole positions, could then be selected and counted. His Tabulating Machine Company (1896) was a predecessor to the International Business Machines Corporation.  Electric Tabulating Machine:  Early United States censuses were tabulated by hand, a process that took years. The electric tabulating machine, invented by American engineer Herman Hollerith and first used in the 1890 U.S. census, dramatically reduced the time and effort required to process census data. To use the machine, census clerks converted responses on census questionnaires to holes punched in predetermined locations on paper cards. When pins in the card reader passed through the holes, an electrical circuit was completed that activated the appropriate mechanical counters.

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