This computer is not authorized

When I try to play Raymond's video G&B #3, I get a pop up message from Apple saying:

This computer is not authorized to play "gb3.mov".

If you purchased this song you can open iTunes and authorize this computer to play this song by entering you Apple ID and password.

Then it prompts me to open iTunes. Guess that I too need to purchase the song that Raymond used if I want to hear it. Is that right?

My first encounter with Apple's Digital Rights Management (DRM) ...