In Other Worlds: SF and the Human Imagination
By Margaret Atwood
Barnes & Noble link
(Fun fact: the main reason I joined Twitter was because Margaret Atwood had one and enjoyed using it.)
When you want to learn about a genre, you normally go towards the genre's representative books. In this case, we are talking about science fiction. Go for the popular, we have Robert A. Heinlein, Ray Bradbury, and Philip K. Dick. Wanna get esoteric? Walter M. Miller, C.S. Lewis, and J.G. Ballard. How about the ladies? Margaret Atwood, Octavia E. Butler, and Ursula K. Le Guin. You have a lot to choose from.
In this case, let's go with Margaret Atwood. She has written the chilling The Handmaid's Tale, the apocalyptic tale of Oryx and Crake and its sequel The Year of the Flood. But she ain't through. She has more to say about science fiction than her novels could contain. With In Other Worlds, Atwood puts together all she learned about sci-fi and schools you good.