Who's There?

Knock, knock.

Who's there?

Who.

Who who are you? Are you an owl or something?

Explanation

Experiment

Explain Bear

Alright listen up, slowpoke. The joke is a play on words. The person at the door says "Who," and the other person repeats it. The joke teller then asks if they are an owl, because owls are known to make a "who who" sound. If you didn't get it, it's ok. You're not alone.