A named pipe is an inter-process communication mechanism, which exists both on Unix and Unix-like systems (where it is also known as a FIFO and is file-like), and on Microsoft Windows (where it is an in-memory kernel object). The semantics and APIs differ substantially between the platforms.
Unix
On Unix and Unix-like systems a named pipe (also known as a FIFO for its behavior) is an extension to the traditional pipe concept, and is one of the methods of inter-process communication.
A traditional pipe is "unnamed" because it exists anonymously and persists only for as long as the process is running. A named pipe is system-persistent and exists beyond the life of the process and must be deleted once it is no longer being used. Processes generally attach to the named pipe (usually appearing as a file) to perform inter-process communication (IPC).
Windows
On Windows operating systems a named pipe is a named kernel object which provides duplex data transfers between two processes, a pipe server and a pipe client. Multiple completely independent instances of a particular named pipe object can be created, each connecting the pipe server to exactly one client. A pipe instance persists only as long as its server and client processes keep a handle referencing it.
Communication between the server and client via a pipe instance may be either stream-oriented or message-oriented.
