(IPC) Exchange of data between one process and another, either within the same computer or over a network. It implies a protocol that guarantees a response to a request. Examples are Unix sockets, RISC OS's messages, OS/2's Named Pipes, Microsoft Windows' DDE, Novell's SPX and Macintosh's IAC.

Although IPC is performed automatically by programs, an analogous function can be performed interactively when users cut and paste data from one process to another using a clipboard.