We have always been surprised by Microsoft's great offers and gifts, and this time it was a great offer for users of the Xbox One platforms, which allowed them to get any game in their shop for free, provided that your friend or someone you know already own this game.
Where the person who owns the original game to participate in the program Microsoft Insider in order to experience this new feature, and for those who do not know Insider it allows registered people to get the advantages of the new before the issuance of a final, now that the person who owns the game in the Insider has access to the game store and access to his or her gaming console and will find a new option, Buy as gift, next to play when clicked. This person can send a code via the Xbox Live network or by e-mail to you. Now that he sends you Your friend code, and you can get the game that you land You own code for free, by entering the code that you got from your friend if you want to get a game.
If you originally own games on your Xbox One platform you can also subscribe to insider and get the feature that lets you give code to your friends or you can sell that code to other people or offer it as a mini service to earn some money.
Insider link: Insider link