Interesting tool. I put Intro to Algorithms by Cormen & Surely You're joking Mr. Feynman and got lots of autobiographical books that I wouldn't really pick up

Interesting tool. I put Intro to Algorithms by Cormen & Surely You're joking Mr. Feynman and got lots of autobiographical books that I wouldn't really pick up :). Though there are others which pique my interest somewhat. Out of curiosity, what kind of recommendation system has been used here?