Zynga is a social network game developer located in San Francisco, United States. The company develops browser-based games that work both stand-alone and as application widgets on social networking websites such as Facebook, Orkut, Google+ and MySpace.
As of November 2011, Zynga's games on Facebook have over 200 million monthly active users. Five of Zynga's games, CityVille, CastleVille,Texas HoldEm Poker, FarmVille, and Empires & Allies, are among the most widely used game applications on Facebook, with CityVille having over 54 million monthly active users.
Zynga filed with the SEC to raise up to $1 billion in an initial public offering on July 1, 2011, and began trading on NASDAQ December 16, 2011.