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<p align="center"><font size=6 color="white">History</font></p>
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<img src="imgs\Classic_shot_of_the_ENIAC.jpg" align="right" width=20% height=30%>
The first use of the word "computer" was recorded in 1613 in a book called "The yong mans gleanings" by English writer Richard Braithwait I haue read the truest computer of Times, and the best Arithmetician that euer breathed, and he reduceth thy dayes into a short number. It referred to a person who carried out calculations, or computations, and the word continued with the same meaning until the middle of the 20th century. From the end of the 19th century the word began to take on its more familiar meaning, a machine that carries out computations.
<h2>Limited-function early computers</h2>
The history of the modern computer begins with two separate technologies, automated calculation and programmability. However no single device can be identified as the earliest computer, partly because of the inconsistent application of that term. A few devices are worth mentioning though, like some mechanical aids to computing, which were very successful and survived for centuries until the advent of the electronic calculator, like the Sumerian abacus, designed around 2500 BC[4] of which a descendant won a speed competition against a modern desk calculating machine in Japan in 1946,[5] the slide rules, invented in the 1620s, which were carried on five Apollo space missions, including to the moon[6] and arguably the astrolabe and the Antikythera mechanism, an ancient astronomical computer built by the Greeks around 80 BC.[7] The Greek mathematician Hero of Alexandria (c. 10–70 AD) built a mechanical theater which performed a play lasting 10 minutes and was operated by a complex system of ropes and drums that might be considered to be a means of deciding which parts of the mechanism performed which actions and when.[8] This is the essence of programmability.
Around the end of the 10th century, the French monk Gerbert d'Aurillac brought back from Spain the drawings of a machine invented by the Moors that answered either Yes or No to the questions it was asked.[9] Again in the 13th century, the monks Albertus Magnus and Roger Bacon built talking androids without any further development (Albertus Magnus complained that he had wasted forty years of his life when Thomas Aquinas, terrified by his machine, destroyed it).[10]
In 1642, the Renaissance saw the invention of the mechanical calculator,[11] a device that could perform all four arithmetic operations without relying on human intelligence.[12] The mechanical calculator was at the root of the development of computers in two separate ways. Initially, it was in trying to develop more powerful and more flexible calculators[13] that the computer was first theorized by Charles Babbage[14][15] and then developed.[16] Secondly, development of a low-cost electronic calculator, successor to the mechanical calculator, resulted in the development by Intel[17] of the first commercially available microprocessor integrated circuit.
<a href="HisTory.html">See-More</a>
<a name="types">
<h2 align="CENTER">Types Of CompuTers</h2>
Computers can be generally classified by size and power as follows, though there is considerable overlap:
<ul>
<li>Personal computer: A small, single-user computer based on a microprocessor.
<li>Workstation: A powerful, single-user computer.A workstation is like a personal computer, but it has a more powerful microprocessor &,in general,a higher-quality monitor.
<li>Minicomputer: A multi-user computer capable of supporting up to hundreds of users simultaneously.
<li>Supercomputer: An extremely fast computer that can perform hundreds of millions of instructions per second.
</ul>
<a name="mini">
<h3>Mini CompuTers</h3>
It is a midsize computer. In the past decade, the distinction between large minicomputers and small mainframes has blurred, however, as has the distinction between small minicomputers and workstations. But in general, a minicomputer is a multiprocessing system capable of supporting from up to 200 users simultaneously.
<h3>WorksTations</h3>
It is a type of computer used for engineering applications (CAD/CAM), desktop publishing, software development, and other types of applications that require a moderate amount of computing power and relatively high quality graphics capabilities. Workstations generally come with a large, high-resolution graphics screen, at large amount of RAM, built-in network support, and a graphical user interface. Most workstations also have a mass storage device such as a disk drive, but a special type of workstation, called a diskless workstation, comes without a disk drive. The most common operating systems for workstations are UNIX and Windows NT. Like personal computers, most workstations are single-user computers. However, workstations are typically linked together to form a local-area network, although they can also be used as stand-alone systems.
<a href = "WorkStation.html"> See More</a>
<h3>Super CompuTers</h3>
Supercomputer is a broad term for one of the fastest computers currently available. Supercomputers are very expensive and are employed for specialized applications that require immense amounts of mathematical calculations (number crunching). For example, weather forecasting requires a supercomputer. Other uses of supercomputers scientific simulations, (animated) graphics, fluid dynamic calculations, nuclear energy research, electronic design, and analysis of geological data (e.g. in petrochemical prospecting). Perhaps the best known supercomputer manufacturer is Cray Research.
<a href = "Supercmp.html"> See More</a>
<h3>Personal CompuTers</h3>
It can be defined as a small, relatively inexpensive computer designed for an individual user. In price, personal computers range anywhere from a few hundred pounds to over five thousand pounds. All are based on the microprocessor technology that enables manufacturers to put an entire CPU on one chip. Businesses use personal computers for word processing, accounting, desktop publishing, and for running spreadsheet and database management applications. At home, the most popular use for personal computers is for playing games and recently for surfing the Internet.
<a href = "PerSonal_CompuTers.html"> See More</a>
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