Store Music Online with Mac's iTunes Match
You will want all of your music to be available on your Mac. You probably didn't get all your music from iTunes. You may have ripped CDs. You may have purchased music from another online service. And you may have obtained it through a file-sharing service whose legal status is dubious.
That's where a premium iCloud feature called iTunes Match fills the bill. The service stores up to 25,000 of your tracks in the cloud, no matter how it was obtained (in most cases), and makes it accessible on up to ten devices and computers, including any of the Macs you own that have iCloud access — that is, as long as they're running Lion or a later version of OS X.
What's more, matched songs that are available in the iTunes Store — where you obtained them doesn't matter — are made available at what is considered to be iTunes Plus quality or 256 kilobits per second. If the song isn't available in the iTunes Store, you'll be able to listen in its original audio quality, which may not be quite as good as if that song were available in the iTunes Store.
Apple charges $24.99 a year for iTunes Match, but if you're a big fan of music and boast a sizable music collection, the fee is well worth it. A bonus of subscribing: iTunes Radio, which is ad-free.
To turn on iTunes Match on your Mac, choose Store→Turn on iTunes Match, and click Add This Computer.
Don't forget to sign in with an Apple ID that's identical to the credentials you used on the first computer you used to set up iTunes Match.
A small cloud icon appears next to any music that's stored in the cloud, as opposed to on your computer. Click the song to download it to your computer so that you can play it when you're offline. With the arrival of iTunes 11, you can also stream that song without having to download it — provided, of course, that you have Internet connectivity.
iTunes Match isn't available in all countries.