ARCHIVED: In Unix, what do the sections of manual pages refer to?

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The Unix manual pages are divided into several sections to speed searches for more experienced users, and to differentiate certain types of information. The usual man page sections are:

  1) User Commands
  2) System Calls
  3) Subroutines
  4) Devices
  5) File Formats
  6) Games
  7) Miscellaneous
  8) Sys. Administration
  l) Local
  n) New
  o) Old

Usually you don't need to worry about which section a manual page will be in. However, sometimes there are manual pages by the same name in different sections, referring to different things (e.g., the manual page on how to use the "hostname" command may be found in section 1 "[User Commands]", while the man page that describes the process of hostname resolution is found in section 5 "[File Formats]"). So, if you want to know how hostnames are resolved, you must type:

  man 5 hostname

Otherwise, you'll get the default page in section 1.