With anything that’s worth learning, there’s always a bit of theory to go along with something more practical, and this book is no exception. Neo4j is the leading graph database (or at least that’s how they describe themselves, anyway), but what does that mean? If you’re from a more traditional relational-database approach, then the concept of a graph database may be a new one, but learning a bit of theory will be worth it. Graph databases have many advantages, one of which is making some queries that are close to impossible in traditional SQL based databases, very possible using a graph database. Graph databases make this possible because their primary function is to relate data. If you understand graph databases already, you could skip ahead, but my teachers always used to say: "Well it’s a good refresher for you," so I’ll say the same, and hopefully there’s a benefit.