https://www.gamespot.com/articles/new-xbox-one-backwards-compatible-game-out-now/1100-6457798/

Xbox One's backwards compatible library continues to grow little by little. Microsoft's Major Nelson announced on Twitter that one more Xbox 360 game is now playable on the current-gen system, and it's a particularly notable one.

Beginning today, Call of Duty 4: Modern Warfare is backwards compatible on Xbox One. The game originally launched for Xbox 360 in 2007 and kicked off the Modern Warfare subseries, which took the Call of Duty franchise out of its usual WWII setting and into more modern-day conflicts. You can read more about the first-person shooter in our original Call of Duty: Modern Warfare review.