Manual pages, or "man pages", are the classic form of UNIX and Linux reference documentation. Ideally, you can look up the man page for any command, configuration file, or library routine. In practice, Linux is free software and some pages haven't been written or are showing their age. Nonetheless, man pages are the first place to look when you need help.

To access a man page, simply type man followed by your topic of inquiry. A pager will be started, so you will need to press q when you're done reading. For example, to look up information about the ls command, you would type:

$ man ls