(1) One of the subsystems or combinations of subsystems that make up an overall system; for example, the accounts payable segment of a financial system.~(2) In storage allocation, a self-contained portion of a computer program that can be executed without maintaining the entire program in main storage.~(3) A collection of data that is stored or transferred as a unit.~(4) In path analysis, a sequence of computer program statements between two consecutive branch points.~(5) To divide a system, computer program, or data file into segments as in (I), (2), or (3).