The width and clock rate of the data bus determine its data

rate (the number of bytes per second it can carry), which is

one of the main factors determining the processing power of a

computer. Most current processor designs use a 32-bit bus,

meaning that 32 bits of data can be transferred at once. Some

processors have an internal data bus which is wider than their

external bus in order to make external connections cheaper

while retaining some of the benefits in processing power of a

wider bus.