Blizzard Entertainment, Inc. is an American video game developer and publisher based in Irvine, California, and is a subsidiary of the American company Activision Blizzard. The company was founded on February 8, 1991, under the name Silicon & Synapse by three graduates of the University of California, Los Angeles Michael Morhaime, Frank Pearce, and Allen Adham. The company originally concentrated primarily on the creation of game ports for other studios before beginning development of their own software in 1993 with the development of games like Rock n' Roll Racing and The Lost Vikings. In 1994 the company became Chaos Studios, then Blizzard Entertainment, Inc. after being acquired by distributor Davidson & Associates.

Shortly thereafter, Blizzard released Warcraft: Orcs & Humans. Blizzard went on to create several other video games, including Warcraft sequels, the Diablo series, the StarCraft series, and in 2004 the massively multiplayer online role-playing game World of Warcraft. Their most recent projects include the first expansion for Diablo III, Reaper of Souls, the online collectible card game Hearthstone: Heroes of Warcraft, the sixth expansion for World of Warcraft, Legion, the multiplayer online battle arena Heroes of the Storm, the third and final expansion for StarCraft II: Wings of Liberty, Legacy of the Void, and the multiplayer first-person shooter Overwatch.

On July 9, 2008, Activision merged with Vivendi Games, culminating in the inclusion of the Blizzard brand name in the title of the resulting holding company. On July 25, 2013, Activision Blizzard announced the purchase of 429 million shares from majority owner Vivendi. As a result, Activision Blizzard became a completely independent company.