Learn Linux Shell Scripting - Fundamentals of Bash 4.4

Pipes

Finally, the moment we've all been waiting for: pipes. These near-magical constructs are used so much in Linux/Bash that everyone should know about them. Anything more complex than a single command will almost always use pipes to get to the solution.

And now the big reveal: all a pipe really does is connect the stdout of a command to the stdin of another command.

Wait, what?!