So here's the thing: Books are frikkin awesome. They are (imo) the best way to tell a story in nearly every case. And thus, just like I have favourite games and game series, I have favourite books, and book series.
So here's some of my faves:
Gone series (Michael Grant)
Discworld novels (not really a series, just a bunch of books set in the same universe) (Terry Pratchett)
Percy Jackson/Heroes of Olympus series (Rick Riordan)
Sean King and Michelle Maxwell series (David Baldacci) (also I couldn't find a good pic of all covers, so I went with only one of the books)
More series/books (can't include too many pics lol):
Artemis Fowl series (Eoin Colfer)
Harry Hole series (Jo Nesbø, Norwegian writer. Y'all should check him out )
Harry Potter series (J. K. Rowling)
Proxima "not yet a" series (Stephen Baxter)
Mission Telemark (Amanda Mitchison)