Game Series Face off Vol.5 Forza or Gran Tursimo

Forza

Forza Motorsport (Italian for "Force", commonly referred to as Forza) is a popular and critically acclaimed series of racing simulation video games for the Xbox and Xbox 360 developed by Turn 10 Studios and published by Microsoft Studios.
Forza seeks to emulate the performance and handling characteristics of a large number of real-life production, modified and racing cars. Unlike the similar PlayStation franchise Gran Turismo, Forza has much more emphasis placed on the modification and customisation of vehicles. Despite these differences, Forza is often seen as Microsoft's answer to Gran Turismo for the Xbox systems.
As of February 2010, the Forza games have sold over 10 million copies since the release of Forza Motorsport in May 2005.
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Gran Tursimo

Gran Turismo (グランツーリスモ Guran Tsūrisumo?, Italian for "Grand Tourer" or "Grand Touring", abbreviated GT) is a popular and critically acclaimed series of racing simulation video games developed by Polyphony Digital.
Developed exclusively for PlayStation systems, Gran Turismo games are intended to simulate the appearance and performance of a large selection of vehicles, nearly all of which are licensed reproductions of real-world automobiles. Since the franchise's debut in December 1997, over 70 million units have been sold worldwide for the PlayStation, PlayStation 2, PlayStation 3, and PlayStation Portable, making it the highest selling video game franchise under the PlayStation brand.
Gran Turismo can trace back its origins to 1992, when Kazunori Yamauchi set out with a group of seven to develop the original Gran Turismo, which took five years to complete.