Where is the sign "?" in HTML?

Question

HTML

I know that the "?" - used to indicate that the version of the stylesheet or image is at the end of the paths. But I didn't see it in the documentation. Where did it come from? Is this described in any documentation?

Answer 1

https://yandex.ru/search/?text=what+is+URL&l10n=...
https://ru.wikipedia.org/wiki/URL#URL_Structure