What's the Difference Between Science Fiction and Non Fiction?

People start niched down their own search. And when they do that, they start to get to what they're actually looking for and what they actually want. If i'm raking number one for the term syphi military earth invasion, if i'm making a lot of those searches, i'm making those sales. There are certain things that shoppers use when searching for non fiction books which can help build the bigger picture with key words.