When playing a video game, every object that you see or interact with resides in what is known as a Level. In Unreal Engine 4 terms, a Level is made up of a collection of Static Meshes, Volumes, Lights, Blueprints and more all working together to bring the desired experience to the player. Levels in UE4 can range in size from massive terrain-based worlds to very small levels that contain a few Actors.