Digital music player is an electronic device used to store music as digital (numeric) code and then to play back the music. Most players are battery-powered and small enough to fit in a shirt pocket. They usually feature a small screen that displays such information as the song title and artist or composer. Listeners choose and play their selections by pressing buttons on the device. Most people listen to the players using small headphones. However, a listener may also connect the player to a stereo system by means of an adapter cable.