In 2015 Microsoft made a stunning announcement that the #Xbox One would provide #backwards compatibility for #Xbox 360 games. Both digital downloads and original Xbox 360 games can now be officially played on the Xbox One.
You must run an updated dashboard to support backwards compatibility on your Xbox One. Regardless of whether your Xbox 360 game is on disc or a digital download, each Xbox 360 game must be re-downloaded from Xbox Live to include an Xbox One specific package. Backwards compatible games should appear automatically in your list of games on Xbox Live as ready to download.
More great news is that you can use your old save files from your original Xbox 360 game play. Simply copy the Xbox 360 files to your cloud storage and Xbox One can automatically use them. This is great for games that are part of an ongoing series. You won’t have to go back and replay some of those older games while waiting for a next installment in the series.
Eurogamer.net have done extensive testing of major titles ported to Xbox One showing some mixed results. Game play holds up and is generally improved for most titles such as Fallout 3, Witcher 2 and Assassins Creed 2 while Halo Reach was considered nearly unplayable due to unstable performance.
Here is the full review and testing of Xbox One backwards compatibility.