What is the purpose of a trigger collider in Unity?

The purpose of a trigger collider in Unity is to detect when other objects enter or exit its area. Unlike regular colliders that physically block and interact with objects in a way that can result in a physics response (like bouncing off or being blocked), a trigger collider serves a different role. It acts as a sensor that detects overlapping interactions between itself and other colliders without causing physical collisions.

When another collider enters, stays, or exits a trigger collider's space, Unity's physics system can invoke specific events, such as OnTriggerEnter, OnTriggerStay, and OnTriggerExit. This allows developers to implement various game mechanics, such as detecting when a player enters a zone to trigger a cutscene, collect items, or initiate gameplay elements without interfering with the physics simulation of the objects involved.

This functionality is essential for gameplay features like area detection, initiating events, and managing interactions in a way that maintains the flow and experience for the player.