A story is more interesting when the reader learns something they didn’t know. Learning should be enjoyable and picking up a few facts in a novel is always a bonus on top of a good story.
I could easily go on a rant right now about how important I believe it is to keep your facts straight in your fiction, but that really isn’t my intent, at least in this blog. What I’m talking about are little tidbits, perhaps in the trivia category, the the reader didn’t know before. This can be about a remote subject, profession, or historical situation.
To be most effective, it needs to be tied into the plot in some manner. One easy way is to give your protagonist an interesting career or hobby. But remember to keep you facts straight. It’s usually best if it’s something about which you already have some knowledge. For example, I like to sneak some astrology into my stories. If you enjoy research, like I do, then the possibilities are endless.