Areas are oblong-shaped collision zones which can trigger callbacks when the player or other objects enter them; they are also often used as position markers for things spawned in code such as sounds or particle effects.

HPL3 ships with several different area types - here's a quick summary of them and of some of their properties.

The most commonly used type of area, used for all sorts of purposes.

If true, this area acts as a blocker for AI seeing the player.

Collision callbacks - for example, if you set CC_Entities to player and CC_Funcs to TriggerHitArea then TriggerHitArea will be called in your map script whenever the player enters or leaves the area.

Called when the player has the area on-screen. Various other properties in the same section modify exactly when that happens.

Makes the area interactable, and triggers this callback when the player interacts with it. You can also set CustomInteractIcon etc.