'What's the best game dev educational resource you've ever used?'

There's a lot of great educational resources out there that can help you refine your game development skills -- the trouble is knowing where to look. Today, we took to Gamasutra's Twitter to try and get a better sense of what tools and techniques contemporary developers use to hone their craft. We collected many of the best answers below, culled from the responses of game developers in all corners of the industry. Whether working as a hobbyist, triple-A developer, indie or otherwise, there should be something here that can help you polish your skills and improve your art. Want to check out the resources other devs recommend below? They're linked below the Tweets which recommend them, so you can quickly check them out yourself (Note: the book links go to Amazon US.) Incidentally, A Theory of Fun by Raph Koster got the most mentions -- hence its cover image appearing alongside this story. Did your favorite resource make the list? If not, share it with Gamasutra's readers in the comments below. And as always, if you'd rather not be included in this story, just tweet at us: @Gamasutra.