cheat

cheat allows you to create and view interactive cheatsheets on the command-line.
It was designed to help remind *nix system administrators of options for commands
that they use frequently, but not frequently enough to remember.
Source comes from https://github.com/cheat
Bugreports for upstream go to: https://github.com/cheat/cheat/issues
Bugreports for snap go to: https://github.com/cheat/snap/issues