A driver is a piece of software that enables the brain of your computer to communicate with its arms and legs i.e. the bits of hardware that are attached.
Every manufacturer of computer components provides a 'driver' for their product – usually accessible via manufacturer’s website. Computer components include video card, network card,
For example, if you had to install a new ASUS P5K motherboard you will need to visit the ASUS website and go to either the "support" area or the "download" area. Then you will need to identify the model number of the motherboard (in this case P5K) and proceed to all the drivers that can be downloaded, see below.
Very often when a component in your computer does not work, it is a driver problem. The driver may not be installed or an incorrect driver is installed.
If a component does not work check the “Device Manager” inside the System Icon in Control Panel. If you see a yellow circle with exclamation mark then there is a driver problem with that component.
Try removing and reinstalling the component.
When a computer has an operating system (e.g. Windows XP) reinstalled, usually the case is that although the computer boots up and works, there is no sound and the internet dows not work.
What is missing in this instance are drivers for 'audio' and 'LAN' (see above).
When the driver for 'audio' is installed, the computer begins to make sounds again. When the 'LAN' (Local Area Network) driver is installed, the internet will work (on the presumption that the modem is connected to the computer via the LAN port).