World of Warcraft is an online game.
World of Warcraft ( WoW ) is a massively multiplayer online role-playing game ( MMORPG ) released in 2004 by Blizzard Entertainment . With a peak of 12 million subscriptions in October 2010 and Blizzard 's final report of 5.5 million subscriptions in October 2015 , World of Warcraft remains the world 's most-subscribed MMORPG , and holds the Guinness World Record for the most popular MMORPG by subscribers .