Sending multiple lines into a pipe
In most script languages, a pipe is where the output of one command is passed as the input of a second command. It allows the chaining of multiple commands without the need of intermediary files.
Every command has 3 files open by default:
|0||stdin||<||Input into the command|
|1||stdout||>&1||>>&1||Output from the command|
|2||stderr||>&2||>>&2||Errors from the command|
Sending a string into a pipe