Today I studied cryptography and compression, so I'm trucking along. These topics are not on the coaching docs I've seen, but I added them to round out my studies. I'm basically trying to compress a 4 year CS degree into less than 1 year.
It's lossy compression.
Khan Academy has an excellent series on cryptography, and its prerequisite topic, information theory. Links are below.
Some of my notes for your enjoyment:
I've embedded the playlist below.
For links to everything I'm studying, check out my project on github: