Computer Fundamentals History and Generations of Computers some of Early Computers

History and Generations of Computer

History of Computer :

" Who invented the computer? " is not a question  with a simple answer. The real answer is that many inventors contributed to the history of computers and that a computer is a complex piece of machinery made up of many parts, each of which can be considered a separate invention. Charles Babbage commenced the Analytical Engine about 1833.

Generation of Computer :

The real beginnings of computers as we know them today lay with an English mathematics professor, Charles Babbage (1791-1871). By 1812, Babbage noticed a natural harmony between machines and mathematics machines were best at performing tasks repeatedly without mistake. After working on the Difference Engine for 10 years, Babbage was suddenly inspired to begin work on the first general-purpose computer, which he called the Analytical Engine.

First Generation (1945-1956):

Howord H. Aiken (1900-1973), a Harvard engineer working with IBM, succeeded in producing an all-electronic calculator by 1944. It was about half as long as a football field and contained about 500 miles of wiring. The Harvard-IBM Automatic Sequence Controlled Calculator, or Mark 1 for short  was an electronic relay computer. It used electromagnetic signals to move mechanical parts. Electronic Numerical Integrator and Computer (ENIAC), produced by a partnership between the U.S government and the University of Pennsylvania. Consisting of 18,000 vacuum tubes, 70,000 resistors and 5 million soldered joints, the computer was such a massive piece of machinery that it consumed 160 kilowatts of electrical power. John Von Neumann designed the Electronic Discrete Variable Automatic Computer (EDVAC) in 1945 with a memory to hold both a stored program as well as  data. The key element to the Von Neumann architecture was the central processing unit, which allowed all computer functions to be coordinated through a single source in 1951, the UNIVAC I ( University Automatic Computer ), built by Remington Rand,  became one of the first commercially available computers to take advantage of these advances.

Second Generation (1956-1963):

The transistor replaced the large, cumbersome vacuum tube in televisions, radios and computers. As a result the size of electronic machinery has been shrinking ever since. Transistor led to second generation computers that were smaller, faster, more reliable and more energy- efficient than their predecessors. It was the stored program and programming language that gave computers the flexibility to finally be cost effective and productive for business instructions to run a computer for a specific function ( know as program ) were held inside the computer's memory, and could quickly be replaced by a different set of instructions for a different function.

Third Generation (1964 – 1971):

Through transistors were clearly an improvement over the vacuum tube, they still generated a great deal of heat, which damaged the computer’s  sensitive internal parts. Jack Kilby, an engineer with Taxas Instruments developed the integrated circuit (IC) in 1958. The IC combined three electronic components onto a small silicon disc, which was made from quartz. Scientists later managed to fit even more components on a single chip, called a semiconductor. As a result computers became ever smaller as more components were squeezed onto the chip. Another third-generation development included the use of an operating system that allowed machines to run many different programs at once with a central program that monitored and coordinated the computer’s memory.

Fourth Generation ( 1971– Present):

After the integrated circuits, the only place to go was down in size that is large Scale Integration  (LSI) could fit hundreds of components onto one chip. By the 1980’s very large scale integration (VLSI) squeezed hundreds of thousands of components onto a chip. Ultra-Large scale integration (ULSI) increased that number into the millions. It increased their power efficiency and reliability. As opposed to a mainframe computer, this was one powerful computer that shared time with many terminals for many applications, networked computers allowed individual computers to form electronic co-ops.

Fifth Generation (Present and Beyond):

Using recent engineering advances, computers are able to accept spoken word instructions (voice recognition) and imitate human reasoning. The ability to translate a foreign language is also moderately possible with fifth generation computers. The feat seemed a simple objective at first, but appeared much more difficult when programmers realized that human understanding relies as much on context and meaning as it does on the simple translation of words.