let us know about computers in detail

what are computers?
there is something about computers thats is both fascinating ans intimidating. They are fascinating when they are used in rocketry and space research ,and when they enable men to get to the moon and back.Many people think of them as almost human machines with "brains" thats allow them to think .After all there are computers which play "music" and "speak".On the other hand, we are inclined to be intimidated by their complex mechanisms and the involved scientific principles upon which they are built .
In fact computers do not have brains ans they cannot really think for themselves.They are primarily machines for doing arithmetic operations.They are automatically controlled and do work of many human beings at fantastically high speeds.The are really important thinking is done by humans who feed them with the information and program them to perform particular operations with the information they are given.
Although primarily a calculating machine ,the modern computer can also store up a vast mass of information .It can be programed to carry out "logical"operations ,such as transferring certain information from one point of the machine to another ,sorting this information and comparing it with other pieces of information or using it in arithmetic calculations.


HOW COMPUTERS DEVELOPED

To think that computers have suddenly arrived on the scene would be wrong ,although it is true that their number and use have gently increased during recent years .Desk calculators have been in use for a very long time,and even in the days of the old navigators and astronomers there was a need for some sort of calculating instruments to relieve the human brain of work.
The first mechanical calculator was produced by the "Blaise pascal" in 1964.Others tried to improve on it but not until nineteenth century was any real progress made.In 1801 a frenchman named "Jacquard " invented a punch card system for controlling the threads on his weaving looms."Charles Babbage" followed in 1833 with his "analytical engine",which performed calculations automatically, using punched cards.This was the first digital computer.The American Hollerith system also used punched cards ,but the calculating machinery was operated by electro magnetic means .It was introduced in 1889 and was generally used in a highly developed form,right up to the wide spread introduction of electronic computers in the 1950's.
1943 saw the need for computing artillery firing charts and ENIAC(ELECTRONIC NUMERICAL INTEGRATOR AND CALCULATOR) was born. EDSAC(ELECTRONIC DELAY STORAGE AUTOMATIC CALCULATOR) was first introduced at Cambridge university six years later.And so the modern electronic computer came into being.

The pre-history of computers

Our PC’s have “spiritual roots” going back 350 years. Mathematicians and philosophers like Pascal, Leibnitz, Babbage and Boole laid the foundations with their theoretical work.

The Frenchman, Blaise Pascal, lived from 1623-1662, and was a mathematical genius from a very young age. As an 18-year-old, he constructed a calculating machine, and his mathematical theories have had enormous significance to all later scientific research.

The Englishman, George Boole (1815-1864), was also a natural talent. He grew up in very humble surroundings, and was largely self-taught.

When he was 20 years old, Boole founded a mathematics school and then began to develop the symbolic logic which is currently the cornerstone of every program.

Another Englishman, Charles Babbage, began developing various mechanical calculating machines in 1823, which are today considered to be the theoretical forerunners of the computer. Babbage’s “analytical machine” could perform data calculations using punched cards. The machine was never fully realised; the plan was to power it using steam.

construction drawing for one of Babbage’s calculating machines, which consisted of several tons of brass machinery.

Charles Babbage (1791-1871) and his staff constructed various programs (software) for his calculating machine. Babbage is therefore called the ”father of the computer” today.

However, it was only in the 20th century that electronics advanced sufficiently to make practical exploitation of these theories interesting.

The Bulgarian John Vincent Atanasoff (1903-1995) is the inventor of the electronic digital computer. Atanasoff was a genius. At the age of nine, he studied algebra with the help of his mother Iva Lucena Purdy, a mathe­matics schoolteacher.

In the 1930’ies Atanasoff was a professor of mathematics and physics at Iowa State University in the USA. Here he used the existing tools like the Monroe calculater and IBM tabulator for his calculations, but he found these machines too slow and inaccurate. For years he worked on the idea that there should better machines for calculation. His thought was to produce a digital machine, since Atanasoff had concluded that mathematical devices fell into two classes, analog and digital. The term digital was not invented, so he called this class of devices “computing machines proper”

In the winter of 1939 Atanasoff was very frustrated from his lack of progress. After a long car ride (Atanasoff was fond of fast cars) he found himself drinking whisky in a bar (he was fond of scotch as well). Suddenly he had the solution. A machine built on four principles. It should work on base-two (binary) numbers instead of base-10 and use condensers for memory. Atanasoff teamed up with a brilliant young electrician Clifford Berry and later the 700 pounds machine called Atanasoff-Berry Computer was developed. This was the first digital computer.

Another pioneer was the German Konrad Zuse (1910-1995). He was only 18 when he constructed his own mechanical binary computer called Z1.

During the Second World War Zuse’s computer Z3 was used in the German aircraft industry. It was the first computer in the world to be programmed with software. It is interesting, that Zuse’s computers were developed entirely independent of other contemporary scientists work.

Konrad Zuse. One of the first scientists to produce working computers.

During the war, the Germans also used an advanced code machine (Fig. 8), which the English expended a great deal of effort on “hacking”. They were successful, and this contributed to laying the foundation for the later development of computing.

An interesting piece of trivia: In 1947, the American computer expert, Howard Aiken, stated that there was only a need for six computers in the entire USA. History proved him wrong.

The German ”ENIGMA” code machine.