PlayerUnknown's Battlegrounds (PUBG) is an online multiplayer battle royale game developed and published by PUBG Corporation, a subsidiary of South Korean video game company Bluehole. The game is based on previous mods that were created by Brendan "PlayerUnknown" Greene for other games, inspired by the 2000 Japanese film Battle Royale, and expanded into a standalone game under Greene's creative direction. In the game, up to one hundred players parachute onto an island and scavenge for weapons and equipment to kill others while avoiding getting killed themselves. The available safe area of the game's map decreases in size over time, directing surviving players into tighter areas to force encounters. The last player or team standing wins the round. Battlegrounds was first released for Microsoft Windows via Steam's early access beta program in March 2017, with a full release on December 20, 2017. That same month, the game was released by Microsoft Studios for the Xbox One via its Xbox Game Preview program, and officially released in September 2018. The same year, a free-to-play mobile version for Android and iOS was released, in addition to a port for the PlayStation 4. Battlegrounds is one of the best-selling and most-played video games of all time, selling over fifty million copies worldwide by June 2018, with over 400 million players in total when including its free-to-play mobile version. Battlegrounds received positive reviews from critics, who found that while the game had some technical flaws, it presented new types of gameplay that could be easily approached by players of any skill level and was highly replayable. The game received several Game of the Year nominations, among other accolades. Several other video games, following in Battlegrounds's success, added battle royale-style modes, while a number of clones, primarily out of China, also appeared. PUBG Corporation has run several small tournaments and introduced in-game tools to help with broadcasting the game to spectators, as they wish for it to become a popular esport.