You didn't think you were ever going to see this heading did you? This chapter has been very long but highly theoretical. We haven't built anything fun and the only code we saw was to exemplify most of the things we talked about. It was a difficult chapter as it covered many complex aspects of data storage and handling. But trust me, these things are important to know and this chapter can serve both as a starting point to dig deeper into the code and a reference to get back to when unsure of certain aspects.

We saw what the main options for storing data in Drupal 8 are. Ranging from the State API all the way to entities, you have a host of alternatives. After covering the more simple ways, such as the State API, the private and shared tempstores and the UserData API, we dove a bit more into the configuration system, which is a very important one to understand. There, we saw what kinds of configuration types we have, how to work with simple configuration, how it's managed and stored, and so on. Finally, in what is arguably the most complex part of the chapter, we looked at entities, both content and configuration. Just as you were recovering from reading all about how entity types are plugins with so many options, I hit you with the TypedData API. But right after that we put it to good use and saw how we can interact with entities: query, load, manipulate and validate data based on TypedData.

In the next chapter, we will apply in a very practical way a lot of the knowledge we learned in this one, especially related to content and configuration entities, but also plugin types and so on. So, that should be much more enjoyable, as we are going to create a new module that actually does something useful.