This presentation explores the last built-in (as opposed to user-defined) types in this course. These types are often used to store data in files.

We actually had an (accidental) sneak peak at these types in the previous presentation, as those recursive functions involved nested lists. But in this presentation we will look at them in more detail, and see what it uniquely tricky about them.

This presentation references Lesson 18 and Videos 19.1-19.7.