With the subject argument, help displays all of the help pages and lower level subjects (if any exist) under the specified subject.
With the subject/helpppage argument, help displays the specified help page. The help output is passed through a simple pager if output exceeds 23 lines, pausing while waiting for a return to be entered. If any other character is entered, the output is terminated.
The help help syntax displays help on the help facility at any directory level.