help (command)

In computing, help is a command in various command line shells such as COMMAND.COM, cmd.exe, Bash, qshell, 4DOS/4NT, Windows PowerShell, Singularity shell, Python, MATLAB[1] and GNU Octave.

[3] The command is available in operating systems such as Multics,[4] Heath Company HDOS,[5] CP/M Plus, DOS, IBM OS/2,[6] eComStation, ArcaOS, IBM i,[7] Microsoft Windows, ReactOS,[8] THEOS/OASIS,[9] Zilog Z80-RIO,[10] Microware OS-9,[11] Stratus OpenVOS,[12] HP MPE/iX,[13] Motorola VERSAdos,[14] KolibriOS[15] and also in the DEC RT-11,[16] RSX-11,[17] TOPS-10[18] and TOPS-20[19] operating systems.

Furthermore it is available in the open source MS-DOS emulator DOSBox and in the EFI shell.

The Multics help command prints descriptions of system commands/active functions and subroutines.

[27] The 4DOS/4NT help command uses a text user interface to display the online help.

Windows PowerShell includes an extensive, console-based help system, reminiscent of man pages in Unix.

Its syntax is: HELP is a DCL utility that contains information on the use of commands and descriptions of some OpenVMS concepts such as time formats and lexical functions, as well as lists of commands for a particular purpose (HELP Hints).