In this chapter, we investigated the main plugin types: those dealing with users and how they access the platform and also plugins managing learning and the interactions learners experience in a course. We also looked at the less obvious plugin types, such as text filters and text editor plugins. Remember that the "M" in Moodle stands for modular: if there is an adaption or new feature you need then there is probably a plugin available--or one we can develop--to implement it.
In the next chapter, we study Moodle's internal APIs in more detail, experimenting with the main interfaces as we begin to develop our Resilience platform. We start with accessing data through the Data manipulation API.