The most important part, also called the Central Processing Unit or CPU, is a box that includes many pieces that are not particularly relevant to us at this time. These pieces, inside of the box, perform the jobs of the computer. One of the assignments of this unit is to join all the other pieces connected to it. Another job of this unit is to perform calculations, exactly the same types of calculations you were performing in primary school, except that this box can handle them very (extremely) fast, so fast that there is no human being who can match that speed. Besides the calculations, this unit also performs other assignments that it receives from various sources including you and the external units that are connected to the CPU.



The Monitor

The monitor is the video display you will be looking at, most of the time, to evaluate your work, find out whether the assignments are being carried out satisfactorily. A monitor is largely controlled by some pieces of hardware inside of the computer. But the monitor itself is mainly used to display your work in a graphical setting you can easily interpret. To display what is going on with the computer, the monitor is connected to the computer using a cable. The connection is usually done from the back of both machines:

Monitors come in different sizes. The (most important) size of the monitor is measured diagonally on the screen and is given in inches:

Based on this, monitors range in sizes of 12", 14", 15", 17", 19", 21", 24', or 29", etc. Monitors are also characterized by the flatness of their screen. The flatter and the wider screens are usually the better.



The Keyboard

A computer keyboard is a wide object that is equipped with buttons on which there are letters and numbers:
To distinguish them from other objects, and to synchronize their names with other objects that use similar settings, such as the piano, the buttons on the keyboard are called keys.
From now on, unless specified otherwise, throughout this site, the word "key" refers to the objects you see on the computer keyboard.
To provide a better management, the keys on a keyboard are divided in sections. This arrangement is by convention so the users would be familiar with them and be able to use any keyboard they come in contact with

 The Mouse

A mouse is an object that is meant to fit the proportions of a hand and is positioned on the table so the user can move it easily. Like the other parts, a mouse is connected to the computer, usually to the back, by a cable. Nowadays, it is not unusual to have a wireless mouse so that it doesn't need a cable.     

The Peripherals

All the parts we have reviewed so far are usually required for the computer to function. Some other parts, not required, can also be connected to the computer to complement it. A peripheral is an object attached to the computer to help it perform some necessary assignments none of the other parts can handle. In most scenarios, no peripheral is required but nowadays, it is unusual for a computer not to have any peripheral at all. The most used peripherals are the printer, a digital camera, a scanner, a projector, an external drive (such as an external CD burner for an old computer or an external hard drive), etc.