This is one of my favorite subjects. I was a book nerd long before I was a part of any geek culture. Funnily enough I joined the Harry Potter fandom (I’ll explain what a fandom is in F) long before I knew what a fandom was. So my book nerd life led me into the fandom life and…well, once you’re in the fandom life you don’t ever really leave it.
So, a geek can be a geek for books, but a book nerd is not necessarily a geek. Geeks who love books are often members of fandoms based off the books they like, while a book nerd may like many different genres of books and never end up in a fandom at all. There are two ways to tell the difference between a book nerd and a geek.
1) And this one is iffy and I will explain why. The types of books they are reading. Geeks are often seen carrying fantasy, sci-fi and dystopian books. That’s why Harry Potter, Game of Thrones, Hunger Games and Percy Jackson have such huge followings. Ender’s Game is basically a geek must read at this point, though I believe many book nerds have picked them all up for the sake of knowing when the movies/shows came out. This is why this is tricky. A book nerd will pick up a book if the movie looked good so that they can be well informed in their decision of their opinion about the movie. They will not want to offend other book nerds who liked or loved the book(s).
2) This one is usually a telltale sign. How they dress. Now this will sound like a horrible generalization, but I promise you, any geek worth their salt has at least one article of clothing dedicated to what they geek out about the most. For fandom geeks it’s dedicated to their fandom, for gamers it’s their favorite games or classic games. Book nerds look much like any geek adjacent or non geek out there. Or, if they are anything like I was, they dress for comfort, not fashion. And they will always, always have a book on hand.
That is really about all you need to know.