Call of Duty: Black Ops is a first-person shooter video game developed by Treyarch, published by Activision and released worldwide on November 9, 2010 for Microsoft Windows, Xbox 360, PlayStation 3, 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 and the fifth to be set in World War II. It is the third in the series to be developed by Treyarch, and is a sequel to the developer\'s Call of Duty: World at War.
Within 24 hours of going on sale, the game 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. A subtitled version was released in Japan on November 18, 2010. A Japanese-dubbed version was released on December 16, 2010. After six weeks on release, Activision reported Black Ops had earned $1 billion in sales. On August 3, 2011, Activision confirmed that the game had sold over 25 million copies worldwide, making it the best-selling game of all time in the US, UK and Europe. On April 28, 2012, it was leaked that the sequel, Call of Duty: Black Ops II, will be released on November 13, 2012.