# Lesson 2: More common functors

Contents

- Let’s Review
- The IO Functor and
`Text`

- Product types
- The tuple type
- Tuple maps
- An Exercise
- A short digression

- Pair vs tuple
- Another exercise

- Three-tuple
- Coming up

In the last lesson, we looked at the motivation for the `Functor`

typeclass and some common instances, with `Maybe`

, `Either`

, and lists. `Maybe`

and `Either`

take a different number of type arguments, but they are both structured as sum types. We begin this lesson with some more examples and then we will look at some common product types and their `Functor`

instances.