Atmos receivers are audio and video receivers that support Dolby Atmos, which is a surround sound technology developed by Dolby Laboratories. Dolby Atmos technology adds height channels to traditional 5.1 and 7.1 surround sound setups, allowing sound engineers to place individual sounds and effects in a 3D space around the listener. This creates a more immersive and lifelike sound experience that can enhance the enjoyment of movies, music, and video games.