Cheat – An Ultimate Command Line ‘Cheat-Sheet’ for Linux Beginners and Administrators

Cheat is an interactive cheat-sheet application released under GNU General Public License for Linux Command line users which serves the purpose of showing, use cases of a Linux command with all the options and their short yet understandable function.

http://www.tecmint.com/cheat-command-line-cheat-sheet-for-linux-users/