These weren't actually written in 2015 (most of them anyway), but rather I read them in 2015. I went through all the books I read this year, and have ranked them below, as holiday gift ideas for you!
1) The Fish that Ate the Whale
3) The Magic of Reality
4) Double Your Profits in 6 months or Less
5) Red Notice
7) Dream Big
8) Bad Science
9) Stuff Matters
10) Getting Things Done
11) The Adventures of Sherlock Holmes
12) Marissa Mayer and the Fight to Save Yahoo!