Massively multiplayer online role-playing games blend the genres of role-playing video games and massively multiplayer online games, possibly in the form of web browser-based games, in which a very large number of players interact with one another within a virtual world. As in all RPGs, the player assume the role of a character and takes control over many of that character's actions. MMORPGs are distinguished from single-player or small multi-player online RPGs by the number of players able to interact together, and by the game's persistent world, which continues to exist and evolve while the player is offline and away from the game. MMORPGs are played throughout the world. Worldwide revenues for MMORPGs exceeded half a billion dollars in 2005, and Western revenues exceeded US$1 billion in 2006. In 2008, Western consumer spending on subscription MMOGs grew to $1.4 billion. World of Warcraft, a popular MMORPG, has an approximately 7.8 million subscribers at the end of the year 2013. Star Wars: The Old Republic, released in 2011, became the world's 'Fastest-Growing MMO Ever' after gaining 1 million subscribers within the first three days of its launch.