There are two types of files name.example and name.howto where name is the original name of the config file to which this file belongs (like .gitignore.howto).
What they mean:
- name.example: contains some sample contents that will/may be useful and can be used as-is or be edited. It also usually contains a lot of commented lines for optional lines that can be commented in as necessary.
- name.howto: contains comments only which explain how to use the config file. This is intended to be usable as a new plain config file with directions for your collaborators as to how to use the file.