The keyboard:

It is a device that integrates a large number of keys, similar to a typewriter. It also has a number of extra bottoms that perform other specific functions.

The mouse:

It is a pointing device used to facilitate the management of a graphical enviroment on a computer. It is usually made of plastic and is used with one hand.

The screen:

The screen is composed by small lights that turn on and turn off when accessing certain memory location or perform certain instructions.

                     THOSE, ARE THE THREE MAIN

                       ELEMENTS OF HARDWARE.