Tuesday, February 19, 2008

Computer Made Easy (1)


What are Computers?

Computers have been around since the Chinese Abacus. They are here to stay. There is a certain feel and flow to the logic that directs their activities.

Electronically, all computers work about the same. Computers vary widely in size and use. However all computers are similar in what the hardware does. So-called microcomputers (like your desktop Personal Computer (PC)) are designed for personal use, relatively low price, and modest data processing tasks.
Minicomputers are moderate sized (a small refrigerator size) and perform more complex tasks with larger amounts of data. Minicomputers might be used in a small engineering office or a local bank branch to send transaction data to a head office computer.Mainframe computers are large, expensive and process billions of characters of data rapidly and fill entire rooms.

Finally, supercomputers are built to minimize distance between circuit boards and operate at very high speed for complex uses such as designing airplanes, animating complex movie sequences graphically or solving complex engineering formulas having billions of steps mathematically. Supercomputers are built for raw speed. SuperComputers are the main servers in the Internet System.

Some terms apply to all computers. INPUT is how data gets into a computer. The keyboard and mouse are familiar INPUT devices. OUTPUT references how data is provided from the computer. A Monitor or printer are good examples of OUTPUT devices.

PRIMARY STORAGE or MEMORY is the computer’s immediate data storage area - usually this is in small integrated circuit chips which hold data ONLY while power is supplied. This PRIMARY STORAGE area is thus temporary. More permanent SECONDARY STORAGE is used when computer power is off or when data overflows primary storage. This is usually floppy or hard disk drives but can include paper tapes, punch cards, or even non-volatile magnetic bubble memories.

A computer system includes computer hardware, software and people. A computer is a device capable of solving problems or manipulating data by accepting data, performing prescribed operations on the data, and displaying the results in the desired form. The computer is a useful tool for data (or Information) Input, storage, processing and output.