Introduction to Computer
Computers are the machines that can perform tasks or calculations according to set of instructions or programs. The term computer is derived from the word compute which means to calculate. Computer is an electronic device that can perform arithmetic and logical calculations faster. The first fully electronic computers, introduced in 1940s, were huge machines that required teams of people to operate. Compared to those early machines, today's computers are not only thousand times faster, they can fit on your desk, lap and even pocket. You must appreciate the impact of computer in our day-to-day life. The computer has been useful in reservation of tickets in Airlines and Railways, payment of telephone and electricity bills, deposits etc.
Advantages of computer
Computers are very fast due to which thousands of job can be performed within a short period of time. Complex mathematical problems and logical operations can be solved by using this computer. As computer is a versatile device, multiple task like communication, graphics, documentation can be done. A huge amount of data can be stored and retrieved as it has high storage capacity.
Disadvantages of computer
Computers are machine hence, they have no brain so they work according to the program instructions set inside it. It is an electronic device and it uses electrical sources to work, so it is very risky to store data and information on the computer independently because some electrical and electronic damages may damage the data. So we have to make regular backup of the data. Since computers are very expensive device, it becomes beyond the capacity of general user. But now a day its price is going down than past. Computers require dustless and temperature maintained environment for best performance.
Characteristics of computer
Some useful technical terms
History of Computer
We are living in the computer age today and most of our day to day activities cannot be accomplished without using computers. Sometimes knowingly and sometimes unknowingly we use computers. Computer has become an indispensable and multipurpose tool. We are breathing in the computer age and gradually computer has become such a desire necessity of life that it is difficult to imagine life without it.
Actually speaking electronic data processing does not go back more than just half a centaury i.e. they are in existence merely from early 1940’s. In early days when our ancestor used to reside in cave the counting was a problem. Still it is stated becoming difficult. When they started using stone to count their animals or the possession they never knew that this day will lead to a computer of today. People today started following a set of procedure to perform calculation with these stones, which later led to creation of a digital counting device, which was the predecessor the first calculating device invented, was know as ABACUS.
ABACUS
Abacus is known to be the first mechanical calculating device. Which was used to be performed addition and subtraction easily and speedily. This device was a first develop Ed by the Egyptians in the 10th centaury B.C, but it was given it final shape in the 12th centaury A.D. by the Chinese educationists. Abacus is made up of wooden frame in which rod where fitted across with rounds beads sliding on the rod. It id dividing into two parts called ‘Heaven’ and ‘Earth’. Heaven was the upper part and Earth was the lower one. Thus any no. can be represented by placing the beads at proper place.
Napier's Bones
As the necessity demanded, scientist started inventing better calculating device. In thus process John Napier’s of Scotland invented a calculating device, in the year 1617 called the Napier Bones. In the device, Napier’s used the bone rods of the counting purpose where some no. is printed on these rods. The bones are a set of vertical rectangular rods, each one divided in 10 squares. John Napier is also the inventor of logarithms, a concept used to change multiplication into addition. Napier's bones was very successful and was widely used in Europe until mid 1960's. It is mainly used for multiplication table. These rods that one can do addition, subtraction, multiplication and division easily.
Slide Rule
The Slide Rule is an analog device for performing mathematical computations. The first slide rule was created by British mathematician, William Oughtred in 1620. His device was based on the log arithmetic scale created by British astronomer, Edmund Gunter in 1620, Gunter's work, in turn, was based on the principal of logarithm set forth by Scottish mathematician John Napier in 1614. A simple slide rule consists of two graduated scales, one of which slips upon other. The scales are devised in such a way that suitable alignment of one scale against the other makes it possible to obtain products, quotients or their function by inspection.
Pascaline
Blaise Pascal had a father who was an overworked and harassed tax commissioner. The young Pascal developed a mechanical calculator to help him with his work. Pascal started to build it in 1632 when he was 19 and three years later he had developed a machine called Pascaline. In this machine, numbers were entered by dialing a series of numbered wheels, and a series of toothed wheels. Each wheel is printed with the numbers from 0 to 9. When the first wheel made a completed turn from 0 to 9, it automatically caused the second wheel to advance to the next number and so on. It could add and subtract by the movement of wheels. The number of calculating capacity of Pascaline was 9, 99, 99, and 999. It could not be used for division and multiplication.
Leibeneith Calculator
In the year 1671, a German mathematics, Gottfried Leibniz modified the Pascal calculator and he developed a machine which could perform various calculation based on multiplication and division as well.
Analitical Engine
In the year 1833, a scientist form England knows to be Charles Babbage invented such a machine. Which could keep our data safely? This device was called Analytical engine and it deemed the first mechanical computer. It included such feature which is used in today’s computer language. For this great invention of the computer, Sir Charles Babbage is also known as the father of the computer.
Difference Engine
Charles babbage in 1823 developed difference engine. Difference engine was first programmable machine ever made. This device was used for solving differential equations. This device has different sections for input, output and storage media. The machine can give results and process it. There are different parts of engine: Input, Mill (processing), Memory, Output ( Results).
Lady Augusta Ada Lovelace
Lady Ada suggested using binary numbers instead of decimal number in Analytical Engine. Lady Ada also wrote a program to be used in Analytical Engine. She is also known as the "First Programmer"in the history of computer science because this was the first program ever written.
Ada met Babbage at a party in 1833 when she was seventeen and was entranced when Babbage demonstrated the small working section of the Engine to her. She intermitted her mathematical studies for marriage and motherhood but resumed when domestic duties allowed. In 1843 she published a translation from the French of an article on the Analytical Engine by an Italian engineer, Luigi Menabrea, to which Ada added extensive notes of her own. The Notes included the first published description of a stepwise sequence of operations for solving certain mathematical problems and Ada is often referred to as 'the first programmer'. The collaboration with Babbage was close and biographers debate the extent and originality of Ada's contribution.
Dr Herman Hollerith
The first person to use punched card practically is Dr. Herman Hollerith. Using the punched card, he developed the tabulating machine or census machine which proved to be very efficient. In 1896, he also established Tabulating Machine Company (TMC). he later founded the International Business Machine Company By merging it with other companies in 1933. After graduation from the Columbia University School of Mines in 1879, Hollerith became an assistant to his teacher William P. Trowbridge in the U.S. census of 1880. During the next decade he taught briefly at the Massachusetts Institute of Technology, Cambridge; experimented on air brakes; and worked for the Patent Office in Washington, D.C.
During all this time Hollerith was occupied with the problem of automating the tabulation work of the census. The complete tabulation of the data from the 1880 census had taken seven years, and the 1890 census aimed to collect even more data, leading some to question if the 1890 census would be complete before the next census in 1900. By the time of the 1890 census, he had invented machines to record statistics by electrically reading and sorting punched cards that had been numerically encoded by perforation position.
Generation of Computer
The history of computer is also referred with its generation. Key technology development that vitally changed the way computers operate, resulting in increasingly smaller, cheaper, more powerful, efficient and reliable devices distinguished the generation of the computer. This division of computer according to the development period, memory, processing speed, efficiency, storage etc. is called computer generation. There are five computer generations:
First Generation (1946-1958)
Vacuum tubes were used for first generation computers for circuitry and magnetic drums for memory. They were very huge and expensive to operate. Due to the consumption of great deal of electricity, it generated a lot of heat that often caused malfunctioning in the system. Example: ENIAC, UNIVAC, MARK-1.
Features of first generation computer
- They used vacuum tubes/valves as their main electronic components.
- Storage capacity was limited to 1 KB to 4 KB.
- They used machine level language for programming.
- Processing speed was in millisecond.
- They used magnetic drum for primary memory.
Drawbacks of first generation of computer
- Difficult in maintenance.
- No facility of linking program.
- Difficult for logical programming.
Second Generation (1959-1964)
The transistors invented in 1947 which was not seen as extensive use, replaced vacuum tubes. The transistor was far superior to the vacuum tube that made computers to become smaller, faster, cheaper, more energy-efficient and more reliable that the first generation computers.eg. IBM 1401, UNIVAC-II, IBM 1620.
Features of second generation of computer
- They used transistors in place of vacuum tubes. 1 transistor=1000 vacuum tubes.
- Speed of processing was increased to microsecond.
- They used magnetic core as primary memory and magnetic tapes as auxiliary memory.
- They were much smaller and more reliable.
- They used assembly language for programming.
Third generation (1965-1974)
The development of the Integrated Circuit (IC) was the major turning point of the third generation computers. Transistors were made smaller and placed on silicon clips called semiconductors that drastically increased the speed and efficiency of computers. It was called integrated Circuit. Eg: IBM 360, PDP-8, etc.
Features of third generation of computer
- Integrated Circuit (IC) replaced transistors. 1 IC=100 transistors.
- Processing speed was increased to nanosecond.
- Semi conductor memory was used instead of magnetic core memory.
- They used high-level language for programming.
- They were smaller, more efficient and more reliable.
Fourth Generation (1975-1990)
The development of microprocessor gave rise to the forth generation of computers. A microprocessor has thousands of integrated circuits builds onto a single silicon clips. The Intel 4004 chips, developed in 1971 is the first microprocessor.
Features of fourth generation of computer
- Microprocessor is used in place of transistors. Very Large Scale integration (VLSI) containing 10/20 LSIs(Large Scale Integration) is called microprocessor.
- Speed of processing is increased to Pico second. Billions of instructions could be processed in a second.
- They are very user-friendly computers which use many high level languages for programming
Fifth Generation Computer (1991-unward)
The fifth generation computers are based on Artificial Intelligence (AI) and are still in development. After 90s computers that support Voice Recognition System (VRS) have been developed.
Features of fifth generation of computer
- These computers will use parallel processor made from super conductors Gallium Arsenide (GaAs)/biochip.
- They will posses Artificial Intelligence (AI).
- They will be able to input in nature language.
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