What does the number at the beginning of the configuration file name mean?

Question

linux

The configuration of some things (Xorg, fontconfig, systemd, etc.) is done with the help of several files, in the name of which there is some number. For example:

$ ls /etc/fonts/conf.avail
10-autohint.conf
10-no-sub-pixel.conf
11-lcdfilter-default.conf
11-lcdfilter-legacy.conf
20-unhint-small-vera.conf
25-unhint-nonlatin.conf
...

What do these numbers mean?

Answer 1

usually - the order of application.

Answer 2

This is used for several purposes: firstly, the file name is uniqueized in this way, and secondly, sorting is done in this way, which in turn is used for the order / priority of loading configs. Less often, numbering is used for application-specific needs, such as specifying a version or a backup marker.