What is multicam editing?

You might not have thought too much about how something like an interview is shot in a way that makes the alternate angles possible, and an edit that looks like more than one camera was used doesn't mean that this was the case; reaction shots are sometimes filmed afterwards and edited into the interview, for instance.

Pay attention to edits you see of live-action music videos, interviews, scenes from movies and series and try to assess whether more than one camera was rolling at the same time.