Manuals
Manuals
[A horizontal line has four points labeled on it, with the second point from the left marked with a dashed vertical line dividing the horizontal line into two parts.] [An arrow labeled "Solve problems" points left from the vertical line.] [An arrow labeled "Create problems" points right from the vertical line.] [The points are labeled, from left to right, "Tools that don't need a manual", "Tools that need a manual", "Tools that need a manual but don't have one", and "Tools whose manual starts with 'how to read this manual'".]

The chart shows the quality of tools regarding their manual:
The title text refers to sudoers , a config file for the unix command sudo . sudo allows users to run a program with elevated permissions, as referenced in 149: Sandwich . Man pages are collections of manuals for different tools, commands, files, and functions on Unix-like systems which can be viewed with the tool man . You can type man man in a terminal to get the manpage for the manual program. See for instance also the comic 912: Manual Override .
The sudoers file specifies which users have sudo access, and which commands they are allowed to run as other users (typically root). The syntax of the file is very complex, and the manpage uses the Extended Backus–Naur Form (or EBNF) to describe the syntax. The sudoers man page starts off with an explanation of EBNF's grammar, which they reference throughout the rest of the man page in describing the syntax of the sudoers file. The sudoers man page is very long, clocking in at 1504 lines. In contrast, the manpages man page only has 566 lines. The number of lines may differ between some distributions and versions.
The title text also notes that the manual's assurance, "don't despair" because "the definitions below are annotated", fails to be reassuring, and instead merely emphasizes the length and complexity of the document to read.
[A horizontal line has four points labeled on it, with the second point from the left marked with a dashed vertical line dividing the horizontal line into two parts.] [An arrow labeled "Solve problems" points left from the vertical line.] [An arrow labeled "Create problems" points right from the vertical line.] [The points are labeled, from left to right, "Tools that don't need a manual", "Tools that need a manual", "Tools that need a manual but don't have one", and "Tools whose manual starts with 'how to read this manual'".]
