Caltech (California) interview questions

A 1.5-day campus visit, where each candidate gets paired with three faculties of interest, and have 30-minute 1-on-1 conversations with them. Among the three faculties, one of them will be an "interviewer" and the conversation is treated like an interview. They basically ask something about the classes you have taken, and then ask you to give a short talk/presentation.

Depends on what you are interviewing for. Typically not bad if you have taken the class previously. Some roles do not need interviews, other roles can be more competitive -- like CS.