help

The help command displays on-line help. To specify information on a particular topic use the syntax:

help topic

If topic is not specified, a short message is displayed about . Topic names can be abbreviated down to the shortest unambiguous string. In case of doubt, help will print out all possible completions. Thus, help f will print all help topics starting with the letter `f'. After help for the requested topic has been given, help for a subtopic may be requested by typing the subtopic name, extending the help request. After that subtopic help has been displayed, the request may be extended again, or pressing return will return one level back to the previous topic. Eventually, the fitting mode prompt will return.

help?