Final answer:
Apple introduced the iTunes Music Store in 2003, which revolutionized the digital music industry by providing a legal platform for downloading music, complementing its iPod.
Step-by-step explanation:
Apple introduced the iTunes Music Store in 2003 as a service to its iPod music player. This launch was significant, as it followed the footsteps of companies like Napster, which initiated music downloading and file sharing, forever transforming how consumers access music and videos. Apple's entrée into the music service realm not only complemented its iPod but also set a standard for legal music downloads, shaping the future of digital media consumption.