Q What exactly is the bus in a computer?

A The term "bus" refers to the collection of circuits and wires which transmit data from one section of a computer to another. In PCs, the bus generally refers to the internal bus, which connects all the internal computer components to the main memory and CPU. PCs also usually have an expansion bus that allows expansion boards to access the CPU and memory.

All buses have two main parts ù a data bus and an address bus. The data bus is responsible for transferring data from memory to the processor. The address bus transfers information, similar to an address, which indicates where the data should go in memory. There is also a bus that carries voltages from the power supply of the computer.

The two most important characteristics of a bus are its size (or width) and its speed. The width of a bus determines how much data can be transmitted at any one time. The greater the width, the greater the amount of data that can be carried, so a 16-bit bus can transmit 16 bits of data at once, while a 32-bit bus can transmit 32 bits of data. The speed of a bus is measured in megahertz (MHz). A fast bus allows data to be transferred quickly, which makes programs ù and your computer ù run faster.