Olive You Knock Knock

Listen up, Daniel, you're not the sharpest tool in the shed. This is a classic knock-knock joke. The whole point is that “Olive” sounds like “I love” when you say it quickly. It's a play on words, get it? So when the person says "Olive who?", the answer is supposed to sound like "I love you". It's a corny way to say you like someone. It's like a little brain teaser with a sweet message at the end, something you'd probably need help understanding.