A hard drive is a device used to permanently store and also retrieve information. There are many variations, but their sizes are generally 3.5 and 2.5 for desktop and laptop computers respectively.
A Motherboard (sometimes known as the mainboard, system board, planar board or logic board) is the main printed circuit board found in computers and other expandable systems. It holds and allows communication between many of the crucial electronic components of a system, such as the central processing unit and memory, and provides connectors for other peripherals.
A sound card (also known as an audio card) is an internal computer expansion card that facilitates economical input and output of audio signals to and from a computer under control of computer programs. The term sound card is also applied to external audio interfaces that use software to generate sound.
A computer fan is any fan inside, or attached to, a computer case used for active cooling, 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 heat sink to cool a particular component.
A computer keyboard is a typewriter-style device, which uses an arrangement of buttons or keys, to act as mechanical levers or electronic switches.
A mouse is a pointing device that detects two-dimensional motion relative to a surface. This motion is typically translated into the motion of a pointer on a display.
A computer monitor is an electronic device that shows pictures. Monitors often look similar to televisions. The main difference between a monitor and a television is that a monitor does not have a television tuner to change channels.