Supersets?

Fellow Blenders, please help.

No matter how much I google and read, I can't fully understand what are supersets. I mean I can quote definitions like “Two exercises combined into one full set, with none to little programmed rest in-between” but that doesn’t help me recognize when I’m doing it with FB :D

How little is “none to little” rest?

Are ALL of their ABAB structured (strength trainig) videos actually supersets?

If yes, why are some videos titled “supersets” (only 11, mostly upper body), what makes them more supersettish than the others?

Not that it’s super(set)important to me, but if there’s a simple explanation I’m missing, I’d love to know it.

Thanks!