Google Play Music, a service available for people who have a Google account, lets people upload their personal music collection and access it instantly on the web.
Upload your personal music collection to a single library, even if it's scattered across multiple computers. You can upload music files from any folder or add your iTunes library and all of your playlists. And when you add new music to your computer, it can be automatically added to your music collection online. More Info »
You can get to your personal music collection on the go with your Android or Apple device. Not online? No problem. The songs you've recently played will automatically be available offline. You can also select the specific albums, artists and playlists you want to have available when you're not connected.
Create your own custom playlists with just a few clicks. Or use Instant Mix to automatically build new playlists of songs from your collection that go great together. Playlists are automatically kept in sync, and you don't have to worry about cables, file transfers, or running out of storage space.