Cryptography

So much of what interests me and consumes the tech industry these days relates to Cryptography, and in particularly public key cryptography. The list would include Heartbleed, NSA spying on citizens, and of course, Bitcoin and Blockhains.

And yet, when I hear people talk about Cryptography or when I read about Cryptography, my eyes tend to glaze over because I never studied Cryptography and am a self taught coder.

So I need to fix this. I want to bone up on Cryptography. Where should I start and what should I read?