Unix based operating systems like Linux offer a unique approach to join two commands on the terminal, with it you can take the output of the first command and use it as input of the second command, this is the concept of pipe or | . Pipes allow two separate process to communicate with each other also if they were not created to do it, so this open an infinite series of opportunity.
A basic example is:
ls -l | grep rwxrwxrwx
This command will print the list of all the files in the local directory that have permission rwxrwxrwx (or that have rwxrwxrwx in their name).
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