With scrolling and automatic text handling, chatboxes do all the work of displaying a character's words for you.
Interactables open a way to explore the world, allowing completion of stages, action triggers, and much more.
As well as representing an environment, rooms dictate the flow of the game and house interactables and NPCs
Non-player Characters (NPCs) help add a source for interaction and story telling to the game. Whether they want to help you or want help from you, they help progress the game.