[40yearoldman]

Languages and English is hard. So asking clear questions is important. Proof is in this conversation. As you seem to have suggested so much from so few words.

It devolved, because it went from what looked like a structured question with a finite expcted result, "Name the most common data structures" , to something more loose, a list of structures, any structures.

Further more, we agree, the candidate was trash, and I don't think the wording would have helped. But I do think a more precise question, or maybe a less loaded, or bias inducing question of "name some data structures". Namely, because "common" is subjective as I pointed out. If you are writing lisp all day, well, list are your most common. If you happen to be in assembly then registers are. So to be a better interviewer you don't want to taint the question with your notions.

[alex_lav]

> If you are writing lisp all day, well, list are your most common.

That's the thing though. _Any data structure is fine_. Say anything!

[randomdata]

Sounds like a trap. The first structure that came to mind was an r-tree. While I have a superficial understanding of when to use one, I have never needed to and would need to look up the details for the next question that is no doubt to talk about it in detail.

It came to mind first because I don’t know the intimate details and would need to look them up should I ever need that structure. That leaves reason to keep the name in active memory, unlike the structures you use daily, which never have reason to communicate outside of artificial situations.