Octave's help command can be used to print brief usage-style
messages, or to display information directly from an on-line version of
the printed manual, using the GNU Info browser. If invoked without any
arguments, help prints a list of all the available operators,
functions, and built-in variables. If the first argument is -i,
the help command searches the index of the on-line version of
this manual for the given topics.
For example, the command
help help
prints a short message describing the help command, and
help -i help
starts the GNU Info browser at this node in the on-line version of the manual.
See section Using Info, for complete details about how to use the GNU Info browser to read the on-line version of the manual.