When it comes to selecting, using, and maintaining a database, it is important to understand its internal design. How to understand the huge sea of ​ ​ distributed databases and tools available today? What are they capable of? How do they differ? Alex Petrov introduces us to the concepts underlying the internal mechanisms of modern databases and storages. To do this, he had to summarize and systematize disparate information from numerous books, articles, posts, and even several open source databases.