Call of Duty: Black Ops is a first-person shooter video game, developed by Treyarch and published by Activision. It was released worldwide on November 9, 2010 for Microsoft Windows, PlayStation 3, Xbox 360, and Wii consoles, with a separate version for Nintendo DS developed by n-Space. Announced on April 30, 2010, the game is the seventh installment of the Call of Duty series. It is also the first to be set in the Cold War, the third in the series to be developed by Treyarch, and is the sequel to Call of Duty: World at War.
Within 24 hours of going on sale, the game had sold more than 5.6 million copies, 4.2 million in the U.S. and 1.4 million in the UK, breaking the record set by its predecessor Modern Warfare 2 by some 2.3 million copies. After six weeks on release, Activision reported that Black Ops had exceeded $1 billion in sales. On August 3, 2011, Activision confirmed that the game had sold over 25 million copies worldwide, making it one of the best-selling games of all time in the US, UK and Europe. A sequel, Call of Duty: Black Ops II, was released on November 13, 2012. Call of Duty: Black Ops III was released on November 6, 2015 as the sequel to Black Ops II.