mp3 is the standard for digital audio. It was mainly developed at Fraunhofer IIS and is the result of many years of team work.
An mp3 file takes up just 10 percent of the storage space of the original. This means music can be quickly transferred over the internet and stored on mp3 players. Depending on its storage capacity, a modern mp3 player stores between 2000 and 200,000 minutes of music, which equates to more than 130 days of uninterrupted music playback. As a result, music fans’ entire collections fit into a device no bigger than a matchbox.
Find more information about the codec's history on http://www.mp3-history.com/.