Computer bus

A Computer bus (often simply called Bus) is part of some computers. Its role is to transfer data, signals or power between some of the components that make up a computer.

Width:The size or width of a bus is how many bits it carries in parallel. Common bus sizes are: 4 bits, 8 bits, 12 bits, 16 bits, 24 bits, 32 bits, 64 bits, 80 bits, 96 bits, and 128 bits. Such buses are in wide use:

• Link between the CPU and on-board Memory.
• Link between multiple CPUs in a multi-cpu system
• Link the Arithmetic logic unit to the rest of the CPU
• Connect hard drives, graphics cards, etc. to the main system.
• Serial ATA, ATAPI, USB and Firewire connections.