Exactly 5 years ago today, Apple launched the iTunes Music Store, which has revolutionized the way music is sold. In those five years, iTunes has become the largest and most successful online music retailer as their competitors failed.
What Apple did right and where the others failed was having a simple price structure, not requiring a monthly subscription fee, letting you keep the music you buy, letting you play the music you buy on multiple computers or other devices, and letting you burn the music to CDs.