Each book in this series comes with a 3.5 inch. MIDI disk of complete professional performances, and includes matching custom arrangements in Easy Piano format. With these books you can: Listen to performances of each song; Play the easy piano arrangements along with the performances; Remove the moelody and play the lead; Sing along with the full performances; Alter tempo to perform at your own pace; Play the easy piano arrangements on their own without the disk. The disk works with any General MIDI keyboard, regardless of the brand. This pack includes 10 favorite carols, including: Christmas Time Is Here * Do You Hear What I Hear * Frosty the Snow Man * Happy Holiday * Happy Xmas (War Is Over) * (There's No Place Like) Home for the Holidays * I Saw Mommy Kissing Santa Claus * Jingle-Bell Rock * Merry Christmas, Darling * Silver Bells.