# 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 and GNU Octave. It provides online information about available commands and the shell environment.

## Implementations

The command is available in operating systems such as Multics, Heath Company HDOS, CP/M Plus, DOS, IBM OS/2, eComStation, ArcaOS, IBM i, Microsoft Windows, ReactOS, THEOS/OASIS, Zilog Z80-RIO, Microware OS-9, Stratus OpenVOS, HP MPE/iX, Motorola VERSAdos, KolibriOS and also in the DEC RT-11, RSX-11, TOPS-10 and TOPS-20 operating systems. Furthermore it is available in the open source MS-DOS emulator DOSBox and in the EFI shell.
On Unix, the command is part of the Source Code Control System and prints help information for the SCCS commands.

### Multics

The Multics help command prints descriptions of system commands/active functions and subroutines. It also prints various information about the system status, system changes, and other general information. This information is selected from segments maintained online, which are in a special format, called information segments. More than 800 information segments are available.

### DEC OS/8

The DEC OS/8 CCL help command prints information on specified OS/8 programs.

### DOS
#### MS-DOS

The help command is available in MS-DOS 5.x and later versions of the software. The help command with a 'command' parameter would give help on a specific command. If no arguments are provided, the command lists the contents of DOSHELP.HLP.
In MS-DOS 6.x this command exists as FASTHELP.
The MS-DOS 6.xx help command uses QBasic to view a quickhelp HELP.HLP file, which contains more extensive information on the commands, with some hyperlinking etc. The MS-DOS 6.22 help system is included on Windows 9x CD-ROM versions as well.

#### PC DOS

In PC DOS 5 and 6 help is the same form as MS-DOS 5 help command.
PC DOS 7.xx help uses view.exe to open OS/2 style INF files (cmdref.inf, dosrexx.inf and doserror.inf), opening these to the appropriate pages.

#### PC-MOS

The Software Link's PC-MOS includes an implementation of help. Like the rest of the operating system, it is licensed under the GPL v3.

#### DR-DOS

In DR-DOS, help is a batch file that launches DR-DOS' internal help program, dosbook.

#### ROM-DOS

Datalight ROM-DOS includes an implementation of the help command. ROM-DOS was introduced in 1989 as an MS-DOS compatible operating system designed for embedded systems.

#### FreeDOS

The FreeDOS version was developed by Joe Cosentino.

### 4DOS/4NT

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

### cmd.exe

Used without parameters, help lists and briefly describes every system command. Windows NT-based versions use MS-DOS 5 style help. Versions before Windows Vista also have a Windows help file (NTCMDS.HLP or NTCMDS.INF) in a similar style to MS-DOS 6.

### PowerShell

In PowerShell, help is a short form (implemented as a PowerShell function) for access to the Get-Help Cmdlet.
Windows PowerShell includes an extensive, console-based help system, reminiscent of man pages in Unix. The help topics include help for cmdlets, providers, and concepts in PowerShell.

### GNU Bash

In Bash, the builtin command help' lists all Bash builtin commands if used without arguments. Otherwise, it prints a brief summary of a command. Its syntax is:

### OpenVMS

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).

## Syntax

The command-syntax is:
Arguments:
* command This command-line argument specifies the name of the command about which information is to be displayed.