Mark Watney is pretty much MacGyver stranded by himself on Mars. He's funny, resilient, and endlessly resourceful. Nothing defeats him and he's always got a plan (even when all the plan amounts to is "figuring out what to do next".) Goes without saying that I really really liked this book. I laughed out loud on many occasion, I was anxious to find out how he was going to survive, I was sad for the other crewmates - I just felt a lot while reading this, and for me that is a mark of a good story. The topic was also interesting to me, and at least for someone with no background in physics the science seemed plausible. I need more contemporary scifi like this.