Polyphony Digital, Inc. is an internal video game developing company of Sony Computer Entertainment and is part of SCE Worldwide Studios. The studio was originally known as Poly's Entertainment, however after the success of Gran Turismo they were granted greater autonomy and their name changed to Polyphony Digital.
The studio is best known for its Gran Turismo racing game series. Led by Kazunori Yamauchi, Gran Turismo became the most successful racing series for the PlayStation and PlayStation 2. The Gran Turismo series is designed to be a real driving simulator, offering realistic driving physics. In 2006, Polyphony released Tourist Trophy, in an attempt to bring the realism of Gran Turismo to motorcycle racing.
Polyphony Digital has also been involved in real life automotive projects. They have developed special versions of their Gran Turismo games for many car manufacturers as demonstrators for their cars. Nissan also commissioned them to design a special bodykit for their 350Z coupe, which first appeared in 'GT Concept: 2002 Tokyo - Geneva' as the "Nissan 350Z Gran Turismo Aero", later becoming the "Fairlady Z NISMO S-Tune Concept by GRAN TURISMO" in GT4. There was also a faster 'Z-Tune' version with minor styling revisions and 400PS. The S-Tune was later sold in real life by NISMO (NISsan MOtorsport) as a tuning package for existing owners.
More recently, they were contracted to design the multifunction display on the new Nissan GT-R, which displays performance information such as G-forces, acceleration opening, brake pedal pressure, steering angle, an "optimal gearshift map," to emphasize economical vehicle operation. When Nissan was looking for a company to develop the GT-R's user-friendly 'multi-function meter', the car maker says Polyphony was the obvious choice because of the simple menu systems applied to video games such as Gran Turismo. "If you think about the GT-R's multi-function meter with the g-force information and everything else, we wanted it to be very easy to read, very easy to use," says Nissan's global vice president of communications, Simon Sproule. "It's really about the logic of how video games work and their menu systems - which anyone can use - and then applying it to the car." 
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