Definition - What does Pipe mean?
A pipe is a method used to pass information from one program process to another. Unlike other types of interprocess communication, a pipe only offers one-way communication by passing a parameter or output from one process to another. The information that is passed through the pipe is held by the system until it can be read by the receiving process.
Pipes are primarily used in programming on Unix systems.
Techopedia explains Pipe
The benefit of using a pipe in Unix or Linux is that it provides for more complex processing. In a Unix shell script, for example, a pipe is specified by a vertical bar (|) in the command line. The result of the first command sequence is used as the input for the second command sequence. Two pipes can be used to enable two-way communication.