The IndyCar Series, officially known as the NTT IndyCar Series for sponsorship reasons, is the highest class of American open-wheel car racing in the United States, which has been conducted under the auspices of various sanctioning bodies since 1920. The series is self-sanctioned by its parent company, IndyCar, LLC, which began in 1996 as the Indy Racing League (IRL) and was created by then Indianapolis Motor Speedway owner Tony George as a competitor to Championship Auto Racing Teams (CART). In 2008, the IndyCar Series merged with CART's successor, the Champ Car World Series, unifying the history and statistics of both series.