 Inter-process communication (IPC) is any mechanism which allows separate processes to communicate with each other, usually by sending messages.Shared memory is strictly speaking also an inter-process communication mechanism, but the abbreviation IPC usually only refers to message passing, and it is the latter that is particularly relevant to microkernels.IPC allows the operating system to be built from a number of small programs called servers, which are used by other programs on the system, invoked via IPC.