I like to tell people that the public key is like an (unlocked) padlock, and the private key is the combination that opens the padlock. It's a little clunky bec

I like to tell people that the public key is like an (unlocked) padlock, and the private key is the combination that opens the padlock. It's a little clunky because the padlock in the analogy only works once, but it conveys the idea of being able to encrypt something securely that you can't then decrypt yourself.