The Xbox racing game series that includes the open-world title Forza Horizon is Forza.
Forza is Microsoft's major racing franchise and includes two distinct branches. Forza Motorsport focuses on circuit racing and detailed vehicle simulation, while Forza Horizon presents an open-world festival setting with road, off-road, and street events.
The first Forza Motorsport launched for the original Xbox in 2005. Forza Horizon debuted in 2012 for Xbox 360 and was developed by Playground Games in collaboration with Turn 10 Studios.
The two branches share car licensing, tuning, and driving systems, but they have different structures. Forza Motorsport is organized around track-based competition, whereas Forza Horizon emphasizes exploration, events, and a broad open-world map.