Man is not the only option for help about a command in linux. whatis — Display a summary of a command (rather than the entire manual) apropos — Display a list of commands that pertain to (are apropos to) a keyword whereis — Display information about the location of a command: the executable, the source code (if any), and the man pages. which — Display which version of a command will execute (for when there are two, or more, commands with the same name installed on the system).