Digital Music Notebook is software for learning how to play music, make musical arrangements, practicing, read music scores and so on. Its interface is very akin to an Internet page, allowing you to navigate in a very intuitive manner. This software lets you find, preview and purchase musical files for viewing, studying and playing along with them. The library of titles available is very comprehensive and includes almost all music genres, styles, artists and instruments. You can search by title, composer, artist, arranger, and even by the mood of the piece.
When playing a file, you can hear the music and see the score and/or tablature, with a bar guiding you through the notes and measures. Also, you can mute any of the instruments of the score and play your own instrument along. For example, if you are a guitarist and download a music piece, you can mute the guitar part of the piece and play your guitar instead (you need to connect your instrument or microphone to your sound card for doing so).
A very cool feature is the "Free downloads", which, as its name implies, lets you download free samples and entire chapters of books. This feature is, by itself, good enough for warrant the downloading of the program.