I always forget what the number after the man pages means.
For example mkfifo(3) (https://linux.die.net/man/3/mkfifo).

This post helps me (and you) to not forget 🙂

MANUAL SECTIONS
    The standard sections of the manual include:

    1      User Commands
    2      System Calls
    3      C Library Functions
    4      Devices and Special Files
    5      File Formats and Conventions
    6      Games et. al.
    7      Miscellanea
    8      System Administration tools and Daemons

    Distributions customize the manual section to their specifics,
    which often include additional sections.

Note: I found out that “man” has a man page of itself. So this is not really necessary anymore. I keep it here for others to find though.

But remember:

$ man man