Have you ever wanted to learn more about Databases but did not know where to start? This is a book just for you. We can treat databases and other infrastructure components as black boxes, but it doesn’t have to be that way. Sometimes we have to take a closer look at what’s going on because of performance issues. Sometimes databases misbehave, and we need to find out what exactly is going on. Some of us want to work in infrastructure and develop databases. This book’s main intention is to introduce you to the cornerstone concepts and help you understand how databases work. The book consists of two parts: Storage Engines and Distributed Systems since that’s where most of the differences between the vast majority of databases is coming from.