Data bus: abstract image of the keyboard of a Commodore 64 personal computer (PC) moving (like a bus) along an abstract urban roadway. In computing jargon, a bus is a pathway for the parallel transmission of data or signals. Some computers have separate buses for data words, control signals (effectively traffic control systems) & addresses (unique numbers for locating memory & disk space). In more sophisticated systems, a single, multi-purpose bus carries all types of traffic, increasing the system's speed & efficiency of operation.