IBM System/360 User Manual

If you want all the available information on a given subcommand,
enter the HELP command and use the subcommand name as an operand. For
example, the following sequence could be used to obtain all the
information available on the DISPLAY subcommand of the OPERATOR command:
READY
operator
OPERATOR
help display
If you want to know only the function, syntax, or operands of the
DISPLAY subcommand you would enter one of the following:
help display function
help display syntax
help display operands
There is one restriction on using the HELP command: you cannot use
it before you use the LOGON command. As explained in the section
"starting and Ending a Terminal Session", LOGON must be the first
command used in your session because it identifies you as an authorized
user of the system.
Note: Your installation can add "help" information to the system by
following the instructions in the publication. Time Sharing Option Guide
to Writing a Terminal Monitor Program or a Command Processor.
20 TOO Terminal User's Guide (Release 21)

IBM System/360 Specifications

General

Brand	IBM
Model	System/360
Category	Desktop
Language	English