An MP3 player is a digital audio player that plays music encoded in the MP3 file format. It's a type of portable music player that allows users to plug in a set of headphones or earphones to listen to the audio, for example, a song or a podcast. They can be inserted into the USB port of a computer; although some are battery powered.
These players not only hold music; they also are storage units that can hold non-audio files. People can then use them to transport basic files from one computer location to another. The Apple iPod is the most popular brand of MP3 player.