Gran Turismo 4 Prologue is a racing video game in the Gran Turismo series. This short version title preceded the release of the full-length version Gran Turismo 4 in 2004. For undisclosed reasons, the game was not released in the North American market. Though it was necessary to limit the number of cars and courses included, this product still included some of the main features of the Gran Turismo franchise such as races, time attack and license tests. The sneak preview also expressed the latest technology Polyphony Digital had accumulated over the past two years. Featuring 50 of GT4's then-planned 500 cars as well as five courses, this expanded demo was designed as a stop-gap until the complete version was released.