The file format is pretty simple. At least for the spreadsheets I create.
As a side note, I love text-based (or extremely simple) file formats. So easy to write tools for them.
# This data file was generated by the Spreadsheet Calculator.
# You almost certainly shouldn't edit it.
let A0 = 45
let A1 = 56
let A2 = @sum(A0:A1)https://en.wikipedia.org/wiki/Apropos_%28Unix%29 : "Often a wrapper for the "man -k" command, the apropos command is used to search all manual pages for the string specified. This is often useful if one knows the action that is desired, but does not remember the exact command or page name."
TBH learning now that "man -k" exists (I don't think I can have "man man"-ed in the last decade) is probably a lot more useful for me.
man -K MANOPT
A far more severe problem IMO is the fact that many Linux distros ship without manpages in their default installs.
Ouch, too much Debian credit, too much Linux credit, even. That's by Bill Joy circa 1977, so it's a BSD Unix thing, widely adopted everywhere else.
Man -k was AT&T's reaction to apropos, IIRC. There is a certain logic to using "man" to search man pages.