GitHub uses Linguist, a "language savant" library for detecting languages in a repository and rendering the language statistics bar on the repository page.
I have a lot of MarkDown-only repositories which serve as reference for me and I don't like how in repository lists and in the repository page they show no language bar.
This is possible to fix using .gitattributes:
https://github.com/github/linguist#documentation
*.md linguist-documentation=false linguist-detectable=trueSometimes the repository may include source code of dependencies or tools which are not to be treated as the source code of the repository itself.
tool/* linguist-vendored