The strange story of Alice and Bob
Alice and Bob are two long-time friends. For most of their lives, they didn't care about cryptography. Actually, they didn't even know what cryptography was. To be totally honest, Bob thought cryptography had something to do with Egypt and archeology.
And they would still happily live without cryptography. I mean, why wouldn't they? However, one special day a strange guy almost died laughing when he heard the youngsters he had just met were named Alice and Bob.
Yeah, the strange guy was a cryptographer. When he stopped laughing, he explained what was wrong with him. Nothing, basically. It's just that he's used to meeting Alice and Bob in cryptographic papers, not in real life. Even in his wildest dreams, he never thought he'd ever meet Alice and Bob in person.