MP3 players are the new handheld music players. First there was the walkman, then CD player, then that little mini disk player, and now there's MP3 player. Instead of using a disk, it uses maybe a memory card or a hard drive, and files can be downloaded into it. You can delete the songs, add more songs, etc. It's pretty much more convenient. The reason they're called MP3 players is because the files that are stored in them are MP3 files.