Most people who spend time on the Linux command line move quickly into using pipes. In fact, pipes were one of the things that really got me excited when I first used the command line on a Unix system. My appreciation of their power and convenience continues even after decades of using Linux. Using pipes, I discovered how much I could get done by sending the output of one command to another command, and sometimes a command after that, to further tailor the output that I was looking for. Commands incorporating pipes – like the one shown below – allowed me to extract just the information that I needed without having to compile a program or prepare a script.
Source:: Network World – Linux