Until now, we never inspected relations between interactions. So, it's time to examine ol.interaction.* classes. All the classes inherit from ol.interaction.Interaction, but compared to controls, it's less simple; you also have subclasses.

See the following diagram to grasp the relationships between the different interaction classes:

An inspection of the above schema shows that every ol.interaction component inherits from ol.interaction.Interaction. In some cases, when an interaction uses a mouse, pen, or touchscreen, it will need to inherit from ol.interaction.Pointer, which deals with this use case.

You can also note with the schema that interactions are tied to touch events for mobile, mouse events like click or drag, mouse events with the mouse wheel, and the keyboard. You can combine them depending on the expected behaviors. Luckily, by default, you can deal with them with ease. Let's see how. After this, we will explore different ways...