What does the "(8)" in fsck(8) mean? *nix commands (and functions?) have a number with them, like `fsck(8)`, `killall(1)`, etc. What does the number mean?

The character explicitly specifies the section that the manual page is part of. On most Unices, the section definitions are as follows:

1. General/user commands
2. System calls
3. Library functions
4. Special files and drivers
5. File formats
6. Games and screensavers
7. Miscellanea and conventions
8. System administration commands, priveleged commands, and daemons
9. Kernel routines



SysV has a similar, but not identical structure:

1. General commands

(M) System administration commands and daemons

2. System calls
3. C library functions
4. File formats and conventions
5. Miscellanea
6. Games and screensavers
7. Special files and drivers



On some systems, the following sections also exist:

* 0 - C library headers
* L - Math library functions
* N - TCL functions/keywords
* X - X-Windows documentation
* P - POSIX specifications