Call of Duty: Modern Warfare 2 is a 2009 first-person shooter game developed by Infinity Ward and published by Activision. It is the sixth installment in the Call of Duty series and the direct sequel to Call of Duty 4: Modern Warfare, continuing the storyline. It was released worldwide on November 10, 2009, for Microsoft Windows, the PlayStation 3, and Xbox 360. A separate version for the Nintendo DS, titled Modern Warfare: Mobilized, was also released on the same day. A version for macOS was developed by Aspyr and released in May 2014, and the Xbox 360 version was made backward compatible for the Xbox One in 2018.

The game's campaign follows Task Force 141 (a multi-national special forces unit commanded by Captain Soap MacTavish as they hunt Vladimir Makarov, leader of the Russian Ultranationalist party), and U.S. Army Rangers from 1st Battalion/75th Ranger Regiment who are defending the Washington DC area from a Russian invasion. The game's main playable characters are Sergeant Gary "Roach" Sanderson, of the 141, and Private James Ramirez, of the Army Rangers, with Captain MacTavish becoming playable later in the campaign. An expansive multiplayer mode is featured in the game, with several new features and modes that were not seen in its predecessor.