Basically, a computer is a machine that can be programmed or instructed to receive an input, analyze, process and produce an output that is useful to the user. The processed information can also be stored. Computers vary distinctively in terms of physical shape and size but in theory they can all execute similar functions. The efficiency of the work done depends greatly though on factors such as the computer’s memory capacity and type of instructions.
The history of computer goes back even to the times of the ancients. Some of the earliest known calculating devices were the abacus, a calculating device invented by the Chinese and the astrolabe which is used in the field of astronomy by the Arabs and Greeks. In the 1200s, the earliest known programmable analog computer was invented by the Arabs. It’s called the “castle clock”. This clock can be adjusted such that it compensate the changing time of days and nights.
In the Renaissance era, Leonardo Da Vinci was claimed to have invented the first mechanical calculator in 1500. After that in 1623, Wilhelm Schickard, a German professor builds arguably the first calculating machine driven by gears, the calculating clock. By 1632, the Slide Rule was invented in England. It was a product from Napier’s bones build by Scotsmen, John Napier in 1617, which enable multiplications via addition (logarithms). In 1642, Blaise Pascal’s adding machine called the Pascaline upstaged DaVinci’s marvel and further push computing technology to a new level. He build it to help his father who was a tax collector.
Several years after Pascal, German Gottfried Wilhelm Leibniz was the first to suggest the use of the binary number system which is important in the way modern computers operate. Then, Joseph Marie Jacquard invented a power loom in 1801 that weaves according to a particular pattern that is registered from series of punched wooden cards which are bounded by a single rope. His technology was particularly popular among mill owners. However, the same popularity caused angry mobs to destroy his looms and even assault Jacquard himself.
By 1822 the English mathematician Charles Babbage was proposing a steam driven calculating machine the size of a room, which he named the Difference Engine. The engine would be a great benefit to oceanic navigation. However the huge funding required to develop and build the device proved too much of a burden for the British government and it was never completed. Babbage next breakthrough would be the Analytic engine, a large programmable device the size of a house which also incorporated Jacquard’s punch card technology. However, the Analytic engine met the same fate as the Difference engine due to the same reason.
In response to the US Constitutions statess' offer of prize for a solution to the automating of census, Herman Hollerith invented a device known as Hollerith desk that successfully made use of Jacquard's punched cards for the purpose of computation. It consisted of a card reader which sensed the holes in the cards, a gear driven mechanism which could count and a large wall of dial indicators to display the results of the count. Hollerith built a company, the Tabulating Machine Company that would eventually became International Business Machines commonly known as IBM, making punched cards become ubiquitous.
IBM made a partnership with Harvard and gave birth to the first programmable digital computer made in the US. The name given was the Harvard Mark I and it came as an answer to the US military request for an automatic form of computation for calculating complex calculation such as the shell trajectory of massive artillery guns. Grace Hopper One of the primary programmers for the Mark I found the first computer "bug". A dead moth that had entered the Mark I and blocking the reading of the holes in the paper tape. The term had since then be used to describe a fault in computer programmes
In 1937, J.V. Atanasoff from Iowa State University and his student made one of the first attempts to invent a fully digital, all-electronic computer. The computer was not programmable but it was the first to store data as a charge on a capacitor and to apply the binary arithmetic system. Another possible forefather of such a modern computer was the Colossus. Known for their excellence in code breaking, intelligence gathering, spying and espionage during WWII, the British build Colossus with the purpose of breaking the cryptographic codes used by the Germans. Colossus was not reprogrammable and its function was limited to code breaking and interpreting.
However, it was the Z3 general purpose computer build by Konrad Zuse that probably won the title of being the first operational, general-purpose, programmable digital computer. It was the third machine from a series of general purpose computers developed bu Konrad Zuse in an war-torn environment lacking resources and manpower. The machine incorporates the programming concept propose by Babbage and binary representation of numbers. All the Z machines perished in Allied bombing with the exception of the Z4 that survive because of it was hauled up into mountains.
ENIAC is usually the awarded as being the grandfather of all-electronic digital computers. It stands for Electronic Numerical Integrator and Calculator. It was build at the University of Pennsylvania between 1943 and 1945 by John Mauchly and J.Presper Eckert.
References
http://www.computersciencelab.com/ComputerHistory/History.htm
http://inventors.about.com/library/blcoindex.htm
http://www.merchantos.com/articles/informational/the-history-of-the-computer/
http://en.wikipedia.org/wiki/Computer
