It's always good when you get something for free and an iTunes download code is no different.
However, as the author of this article found out, when it comes to redeeming your code, things can get ugly and if you're not careful, expensive too.
So before you go and trial and error your way into iTunes debt, have a little read of this short 'How To' to make sure you don't end up paying for something when you don't have to (worst thing ever).
iTunes on your computer
Of course, the fist thing you have to do is fire up iTunes on your computer. Once you've got that open go to the iTunes store and look in the top right hand corner of the page for the Redeem link.
Once you've clicked on the Redeem link things couldn't be easier. You just enter your unique download code into the main box in the middle of the screen and click on the Redeem button.
Once you have done that, whatever your download code was for will automatically start downloading. That's it.
Easy when you know how.
iTunes on your iPhone, iPad or iPod touch
Open the App Store and select Featured from the tabs at the bottom of the screen.
Once the next page has loaded fully, scroll down to the bottom of the page and click on the Redeem button.
A new page will appear where you can enter your download code. Once you've entered your download code click the Redeem button in the top right hand corner of the page and the relevant app will start downloading.