About Digital Music
Online
Online services provide tracks, albums, and videos for purchase via a computer connected to the Internet, and may also be transferred to a portable media player. Some services work directly with other devices, such as a set-top box connected to your television, or a Sony PlayStation 3.
Mobile
Mobile services provide tracks, albums, videos, ringtones and ringback tunes to be acquired and stored on your mobile phone. This category also includes mobile applications or 'apps' that work in conjunction with other, complementary online services on an internet-connected PC, giving you the best of both worlds.
Free with Ads
Some music services are free to use and enjoy, with revenue generated by advertisers rather than music customers — these are commonly referred to as 'Ad-Supported'.
Subscription
If you're a subscription customer, you'll pay a fee, usually monthly, for an online or mobile service that allows you to stream or download a certain number of tracks per month.