A head-up display (HUD) is a technology that projects important information onto a transparent screen in the user's line of sight. This allows users, such as pilots or drivers, to see data like speed, navigation, and other critical metrics without looking away from their primary focus. HUDs enhance situational awareness and can improve safety by reducing distractions. Originally developed for military aircraft, head-up displays are now used in various applications, including commercial aviation and automotive systems. In cars, HUDs can show speed and navigation directions directly on the windshield, helping drivers stay informed while keeping their eyes on the road.