Prior to 1979, the term IndyCar usually refers to cars raced in USAC sponsored races. From 1980 to 1995 the term refers to CART, Championship Auto Racing Teams. From 1996 to 2004, the term can refer either to CART or the Indy Racing League (IRL).
In late 2003 CART was sold to another entity called Open Wheeled Racing Series (OWRS), and the series title was officially changed to Champcar.