(6) Tree Line
The toughest part about reading The Martian will be comprehending its massive amount of scientific information. Weir often spends several pages outlining specific technical details, which can certainly be... a lot. That being said, Weir makes up for with a straightforward, funny writing style that mimics the tone and structure of a blog:
I'm going to be setting a fire. In the Hab. On purpose. If you asked every engineer at NASA what the worst scenario for the Hab was, they'd answer "fire." (4.14-15)
In fact, thanks to this easily digestible writing style, you'll probably even walk away from the novel with a better understanding of science than before... unless you're already a science whiz, in which case we salute you.