About shared music
If your computer is connected to any other computers over a local network (and in the same subnet), and you are using iTunes 4.5 or later, you can share the music in your library and playlists with up to five of those computers. You choose the items you share in the Sharing pane of iTunes preferences.
When you play a shared song, it's streamed over the network to your computer. You can listen to it, but you can't add it to your library or playlists, transfer it to an iPod, or burn it on a CD. You can tell if a song is shared by selecting the song and choosing File > Get Info. If the Kind is "remote" (in the Summary pane), it's a shared file.
You can share spoken word content that you purchase from the iTunes Music Store, but you can't share Audible spoken word content downloaded from Audible.com, or QuickTime sound files. Sharing is intended for personal use only.
Note: If any shared music was purchased from the iTunes Music Store, you can only authorize five computers to play those music purchases.
You can also share a playlist with friends by publishing it as an iMix on the iTunes Music Store. Visitors to the Music Store will be able to see the songs listed in your playlist and play a song preview for any track in your playlist that's also available on the iTunes Music Store.
