25 side by side comparisons of the concepts interviewers ask about most. Understand the tradeoffs, know when to use what, and never confuse the two again.
Evaluation measures quality; RLHF improves it. They are partners, not rivals, you need evaluation to even know whether RLHF worked.
Offline eval runs against fixed datasets before deployment; online eval measures real users after deployment. You need both, and neither is a substitute for the other.