<abbr title =“”> HTML

Question

Hello.
I need help to understand why should I use the <abbr title=“”> if doesn’t do anything. At least that I know.
And if you could, <dfn> tag too.
I would appreciate if someone could explain me in what way is useful this tag.
Thank you very much.

Answer 1

https://www.w3schools.com/tags/tag_abbr.asp

Answer 2

https://html.com/tags/abbr/
https://html.com/tags/dfn/

Answer 3

https://developer.mozilla.org/en-US/docs/Web/HTML/Element/abbr