Hud/ˌeɪtʃ juː ˈdiː/ Definition 1 of 2Pro Tip 1/3Gaming Visibility In video games, HUD elements are vital for quick access to game stats without pausing action. Your ammo count appears on the HUD. Pro Tip 2/3Driving Aid Car HUDs project key data on windshield, aiding focus on the road while driving. The car's speed is displayed on the HUD. Pro Tip 3/3Aviation Tool HUDs in aircraft offer critical flight information at eye-level to pilots for safety. Altitude and horizon level are on the pilot's HUD.