The alternate symbol (vertical bar) on the backslash key, on the standard US keyboard: is known as the pipe. i'm sure more of you didnt know it was called that.
And I can bet most people, have not used it before.
If you are a developer or someone on the unix,linux,macOS side of life,or spend most of your time in the terminal or command-line, you are not most people.
The pipe serves a form of redirection, that channels the output of a command,script or program as input for another set of commands, scripts or program.
command 1's output | command 2 as input
cat text | wc -l
The above example, uses the cat command on a text document and pipes the result of that instruction into the word count wc command with the -l argument to show number of lines.
Usage is not limited too
ps aux | grep 'root'| less
One can daisy chain more of these pipes together to your hearts content.
Thats it for now.