Using this iTunes code generator will give you iTunes codes which you can redeem in the iTunes Store for music, games, apps, movies, tv shows, and books!
The generator works by accessing Apple's servers where the database of iTunes codes are being kept. In this database a code is selected and give to the user, then all they have to do is redeem their free iTunes codes.
So if you've ever wondered how to get free iTunes codes this is it! This is equivalent to a iTunes gift card generator, they both work in the same way.