For instance, a Level 1 would be a more passive experience where you will be able to look around freely, but you will not be triggering or interacting with things in the environment.  A Level 2 will provide some level of interactivity but only very basically, such as being able to move between different scenes in the experience. A Level 3 will start to incorporate some more complex interactions using a remote or controller to trigger things within the scenes. A Level 4 would be a fully interactive experience but something you are still guided through. Finally, a Level 5 would be a fully interactive experience that gives you complete control of how to use it.