>>31709457General recommendations?
Well Heinlein is probably the most readable of the big-3 sci-fi writers. Unfortunately he had a bunch of bizarre ideas about sex that are a bit hard to swallow (or maybe easier to swallow if you're on 4chan all the time). Basically he believed that everyone should have sex with everyone.
Some of the most classic sci-fi stories were written by Isaac Asimov. Mostly in short-story format for those old serial magazines back in the 50's. Some franchises have been built out of those. Arthur C. Clark did some classic sci-fi stories. But he puts christian themes in them. Similar to what the author of Enders Game does (that book is fucking classic).
Sci-fi aside, I recently read this one and liked it. Although it's kind of a self-contained little story that doesn't open up to a wider universe.