An input device, a keyboard uses an arrangement of buttons or keys to input symbols. A central processing unit (CPU) or processor is an electronic circuit that can execute computer programs and has changed dramatically over time but performs the same fundamental operations. A mouse is a small mammal belonging to the rodent order that is also a popular computer pointing device.

1. Parts of the computer a keyboard is an input device, partially modeled after the typewriter keyboard, which uses an arrangement of buttons or keys, to act as mechanical levers or electronic switches. A keyboard typically has characters engraved or printed on the keys and each press of a key typically corresponds to a single written symbol. However, to produce some symbols requires pressing and holding several keys simultaneously or in sequence. While most keyboard keys produce letters, numbers or signs (characters), other keys or simultaneous key presses can produce actions or computer commands.

2. CPU A central processing unit (CPU) or processor is an electronic circuit that can execute computer programs. This term has been in use in the computer industry at least since the early 1960s (Weik 1961). The form, design and implementation of CPUs have changed dramatically since the earliest examples, but their fundamental operation has remained much the same.

3. mouse A mouse (plural mice) is a small mammal belonging to the order of rodents. The best known mouse species is the common house mouse (Musmusculus). It is also a popular pet. The American white-footed mouse (Peromyscusleucopus) and the deer mouse (Peromyscusmaniculatus) also sometimes live in houses. In some places, certain kinds of field mice are also common. This rodent is eaten by large birds such as hawks and eagles. They are known to invade homes for food and occasionally shelter.

4. CPU processor A computer processor is described as idle when it is not being used by any program.

5. CPU FAN A computer fan is any fan inside a computer case used for cooling purposes, and may refer to fans that draw cooler air into the case from the outside, expel warm air from inside, or move air across a heatsink to cool a particular component. The use of fans to cool a computer is an example of active cooling.