HUDs and Burn-in
Prolonged display of HUD elements on certain CRT-based screens may cause permanent damage in the form of burning into the inner coating of the television sets, which is impossible to repair. Also players who pause their games for long hours without turning off their television or putting it on standby risk harming their TV sets. Plasma TV screens are also at risk, although the effects are usually not as permanent.
Burn-in can still happen on LCD monitors, but only when the same image is displayed for weeks.
Read more about this topic: HUD (video Gaming)