War Thunder is a free-to-play vehicular combat MMO featuring aircraft, ground vehicles, and naval craft spanning from the early 20th century to the modern era. Players progress through technology trees across multiple nations, unlocking increasingly advanced military vehicles. The game offers three realism tiers for each vehicle type: arcade, realistic, and simulator modes. Originally developed as a flight simulator under the name "World of Planes," the game expanded to include tanks in 2014 and naval forces later, becoming a combined-arms experience. A mobile version was released in 2023.