help

help: help [-dms] [pattern ...]
    Display information about builtin commands.
    
    Displays brief summaries of builtin commands.  If PATTERN is
    specified, gives detailed help on all commands matching PATTERN,
    otherwise the list of help topics is printed.
    
    Options:
      -d        output short description for each topic
      -m        display usage in pseudo-manpage format
      -s        output only a short usage synopsis for each topic matching
        PATTERN
    
    Arguments:
      PATTERN   Pattern specifiying a help topic
    
    Exit Status:
    Returns success unless PATTERN is not found or an invalid option is given.