If your character can see their health bar or ammo counter just as well as you can, it's a diegetic HUD. This is when a game uses a 'diegetic interface.'Ī 'diegetic interface' can best be described as one where the user interface is incorporated into the actual game lore or in-game objects. So when a game goes out of its way to increase player immersion by incorporating its HUD elements and user interface into the actual fabric and lore of the game world, or eliminating it altogether, it can stand out. This 'HUD' is how the game conveys information to you, and it's become so ubiquitous in games that the very concept often slides beneath notice. If you've ever played a game with a heath meter or ammo counter, you've seen a video game heads-up display.
