The evolution of iTunes

• Release date: April 28, 2003

ITunes traces its history back to 2000, when Apple (AAPL) bought an MP3 player system called SoundJam MP. Apple wisely turned that software into the far more user-friendly iTunes, which debuted alongside the first iPod in October 2001.

The iPod and its companion iTunes software plodded along without any serious traction for a year and a half until Apple released iTunes 4 -- the first version to feature the iTunes Music Store. It was also the first version to be available on Microsoft (MSFT) Windows, opening up iTunes to more than 90% of PC users.

Ten years later, nearly two-thirds of music sales around the world are purchased through iTunes. Apple's software has completely changed the music industry -- and not without controversy.

Apple doesn't keep screenshots of its past iTunes versions, but luckily the folks at OldApps.com are a bit more sentimental. They provided images to CNNMoney.

NEXT: iTunes 5 - DJ, put that record on