PlayerUnknown's Battlegrounds (PUBG) is a multiplayer online battle royale game developed and published by PUBG Corporation, a subsidiary of publisher Bluehole. The game is based on previous mods that were created by Brendan "PlayerUnknown" Greene for other games using the film Battle Royale for inspiration, 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.
The game was 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. A few months later, it was localized and released by Tencent Games in China, while two mobile versions based on the game for Android and iOS were also released. By March 2018, the game sold over forty million copies across all platforms, with the Windows version having sold over thirty million and holding a peak concurrent player count of over three million on Steam, an all-time high on the platform, while the Xbox version sold over five million itself.