How to make a list of people and companies that I want to thank for somehow taking part in the creation of a repo?
A paragraph in README.md? What's the header then?
A special file? How to name it?
I understand that it can't be a rule and I can do it any way I want, but I want to know about common practices. Examples of existing repos will be appreciated!
A common place is indeed in the readme, a separate contributors file which accompanies the project. Optionally and preferentially also shown this list in the application somewhere in the about dialogue or whereever you inform the user about credits and contributors.
If found in the more general credits section, more specifically contributors or authors section it looks somewhat like this).
Alternatively you also often find a separate file like CREDITS.md (e.g. see like this or this) or AUTHORS file (e.g. here) which lists contributors.
