Microsoft Introduces Backwards Compatibility
You will also be able to play online, multiplayer games with your friends even if you're not on the same console. If your friend has the Xbox 360, and you have Xbox One all you need is a copy of a Xbox 360 game and you can play online together.
There is currently no official date of when this will become available or whether or not the Xbox 360 games will be able to carry the 1080p, 60FPS quality that modern Xbox One games support.
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