If you want to do the heavy lifting in understanding Cryptography, almost all the relevant documentation can be found at the following resource. http://csrc.ni

If you want to do the heavy lifting in understanding Cryptography, almost all the relevant documentation can be found at the following resource. http://csrc.nist.gov/publications/PubsFIPS.html http://csrc.nist.gov/publications/PubsFIPS.html A lot of the hard (math heavy) stuff used in modern cryptography has been published almost a couple of decades ago and good books are available on Amazon. I usually just buy them used as you get very good deals for books that have been published several years ago. I would recommend Bruce Schneier's 'Applied Cryptography, Protocols, Algorithms and Source Code in C'. I was surprised to see the 20th Anniversary Edition is out now. https://www.amazon.com/Applied-Cryptography-Protocols-Algorithms-Source/dp/1119096723/ref=sr_1_8?ie=UTF8&qid=1466950028&sr=8-8&keywords=cryptography https://www.amazon.com/Applied-Cryptography-Protocols-Algori... The math involved uses a lot of number theory (prime numbers, prime factorization, modulo computations, chinese remainder theorem, elliptic curves, etc) Once you get a basic understanding of the math, you will find out why it is hard to find the keys (if properly generated) through brute force computer attacks.