Users can understand asymmetric crypto, but the tools are so convoluted for no reason that they usually just give up. I've had no trouble explaining it to "aver

Users can understand asymmetric crypto, but the tools are so convoluted for no reason that they usually just give up. I've had no trouble explaining it to "average" computer users and they got it completely, but then actually using the tools for signing or authentication was the nearly impossible part. Your key has to parts: public and private. You give your public part to the server so it knows it's talking to you because only you have the private part. The server has its own pair and it gives you its public part so you know you're not talking to an impostor server. The private key is never sent, it stays on your computer, but it does some fancy math so the server can know you have it.