http://www.techradar.com/news/original-xbox-games-are-still-coming-to-xbox-one-this-year

Of all the current generation consoles on the market right now, Microsoft’s Xbox One is by far the most impressive when it comes to its commitment to backwards compatibility. 

At the moment there’s an extensive list of Xbox 360 games that can be played on the Xbox One and while that’s continuing to grow, Microsoft announced plans to add original Xbox games into the mix at E3 earlier this year.