A computer is not an acronym and sometimes abbreviated as comp or 'puter. The term "computer" was originally given to humans (human computers) who performed numerical calculations using mechanical calculators, such as the abacus and slide rule. The term was later given to a mechanical device as they began replacing the human computers. Today's computers are electronic devices that accept data (input), process that data, produce output, and then store (storage) the results.

The first digital computer and what most people think of as a computer was called the ENIAC, built during World War II (1943-1946). Early computers like the ENIAC used vacuum tubes and were large (sometimes room size) and only found in businesses, Universities, or governments. Later, computers began utilizing transistors as well as smaller and cheaper parts that allowed the common person to own a computer.

Today, computers help make jobs that used to be complicated much simpler. For example, you can write a letter in a word processor, edit it anytime, spell check, print copies, and send it to someone across the world in a matter of seconds. All of these activities would have taken someone days, if not months, to do before computers. Also, all of the above is just a small fraction of what computers can do.

Desktop computer overview

Below is a picture of a computer with each of the main components that help make up a computer. In the picture, you can see the Desktop computer, Flat-panel display, Speakers, Keyboard, and Mouse. We've also labeled each of the input devices and output devices.

Desktop computer

What components make up a computer?

Today's computers have some or all of the below components (hardware). As technology advances, older technologies, such as a floppy disk drive and Zip drive (both shown below), are no longer required or included with computers.

What parts are needed for a computer to work?

A computer does not need all of the components mentioned above. However, a computer cannot work without having at the very minimum the below parts.

Of course if you had a computer with the above minimum parts for you to communicate with it you would need at least one input device such as a keyboard.


A peripheral is any accessory or add-on that can be attached to your computer, but is not required. For example, a computer printer is a perfect example of a peripheral. See the peripheral definition for a full list of peripherals that can be attached to your computer.

Inside of the computer


A diagram of the back of a personal computer and a brief description of the computer connections can also be found on our connection definition.

Variations of computers

When talking about a computer or a "PC", you are usually referring to a traditional computer that you would find in a home or office. Today, however, the lines of what makes a computer are blurring. Below are all the different examples of what is considered a computer today.


Above, is just a few of the most well-known computers and an example of just how different computers can look today. Below is a complete list of computers of past and present.

Who makes computers?

Today, there are dozens of companies that make and build computers, if you get all of the necessary parts for a computer you can even make your own computer. See our computer companies page for a listing of companies (OEMs) that make and build computers.

Related pages

Also see: Barebone, Compute, Computer family, Computer Hope, Connection, Home Computer, Laptop computer, My Computer, PC, Rig, Server, System unit