Manual Pages
The easiest way to get more information about a particular Linux command or program
is to use the man command followed by the item you want
information on:
This will bring up the manual page ("man page") for the program within the shell,
which have been formatted from the online man pages. These pages can be
referenced from any Linux or Unix shell where man is installed,
which is most systems. Linux includes a built-in manual for nearly all commands,
so these should be your go-to reference.
The manual is divided into a number of sections by type of topic, for example:
| Section | Description |
|---|---|
| 1 | Executable programs and shell commands |
| 2 | System calls (functions provided by the kernel) |
| 3 | Library calls (functions within program libraries) |
| 4 | Special files |
| 5 | File formats and conventions |
| 6 | Games |
| 7 | Miscellaneous (including macro packages and conventions) |
| 8 | System administration commands (usually only for root) |
If you specify a specific section when you issue the command, only that section
of the manual will be displayed. For example, man 2 mkdir will
display the Section 2 man page for the mkdir command. Section 1
for any command is displayed by default.
If your terminal does not support scrolling with the mouse, you can navigate
the man pages by using the up and down arrow keys to scroll up and down or by using the
The man pages follow a common layout. Within a man page, sections may include the following topics:
- NAME
- a one-line description of what it does.
- SYNOPSIS
- basic syntax for the command line.
- DESCRIPTION
- describes the program's functionalities.
- OPTIONS
- lists command line options that are available for this program.
- EXAMPLES
- examples of some of the options available.
- SEE ALSO
- list of related commands.
Example snippets from the man page for the rm (Remove) command:
$ man rm
RM(1) User Commands RM(1)
NAME
rm - remove files or directories
SYNOPSIS
rm [OPTION]... FILE...
DESCRIPTION
This man page documents the GNU version of rm. rm removes each
specified file. By default, it does not remove directories.
If the -I or --interactive=once option is given, and there are more
than three files or the -r, -R, or --recursive are given, then rm
prompts the user for whether to proceed with the entire operation. If
the response is not affirmative, the entire command is aborted.
Depending on the command, the OPTIONS section can be quite lengthy:
OPTIONS
Remove (unlink) the FILE(s).
-f, --force
ignore nonexistent files, never prompt
-i prompt before every removal
-r, -R, --recursive
remove directories and their contents recursively
-v, --verbose
explain what is being done
Fun fact: there is even a manual entry for the man command. Try:
$ man man
Issuing the man command with the -k option will
print the short man page descriptions for any pages that match the command.
For example, if you are wondering if there is a manual entry for the
who command:
$ man -k who
Since there is a man page listed, you can then display the man page for the
who command with man who.