An MP3 player is a portable audio device that replaced tape players like the Sony Walkman and plays computer sound files called "MP3s."

Smaller than pocket transistor radios, and about the size of a cell phone, today's MP3 Players can hold the entire A Course In Miracles audiobook and be played anytime and anywhere from your pillow to your pick-up truck.

They can be used with tiny headphones, with speakers that sit on a table, or through your car stereo.   They run on batteries and have the controls such as Play, Stop, Pause, Fast-Forward, and Rewind.
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