Research

Author's are smart.... at least good authors. They may not know a lot of things but they know how to research. I've heard some of my favorite authors talk about research. In a podcast Brandon Sanderson talked about how much research he did on canals and how they effect the economy for his trilogy Mistborn. This surprised me because when I read them canals weren't a big part of the book. And yet as my sister said the other day, "if the author gets it right the reader doesn't even notice, but if the author messes up it takes you out of the book." At the back of Sarah Eden's books she often writes about the research she did for that book in particular. She seems to get it spot on.
For my novel (that I am still working on), I have researched wolf biology and culture, human hunter gatherers, telling time at night, how far a person can walk in a day, desert animals and plants,  second language acquisition, to name the majority. And it is a fantasy world. That's why historical fiction is so intimidating to me.