6(Real Book Play-Along). The Real Book you know and love has now been updated to include backing tracks for 240 songs on one convenient USB flash drive stick! The play-along CDs alone are worth $100 so this is an amazing package price! The Real Books are the best-selling jazz books of all time. Since the 1970s, musicians have trusted these volumes to get them through every gig, night after night. The problem is that the books were illegally produced and distributed without any reqard to copyright law or royalties paide to the composers who created these musical masterpieces. Hal Leonard is very proud to present the first legitimate and legal editions of these books ever produced. You won't even notice the difference, other than that all of the notorious errors have been fixed!