Plano is a city located in the U.S. state of Texas, mainly within Collin County, but also extending into Denton County. According to the 2000 U.S. Census, the city population was 222,030, making it the ninth largest city in Texas. Plano is within the Dallas–Plano–Irving metropolitan division of the Dallas–Fort Worth–Arlington metropolitan area, a title designated by the U.S. Census, and is colloquially referred to as the Dallas/Fort Worth Metroplex. The city is home to many corporate headquarters, including Dr Pepper/Seven Up, Inc., Electronic Data Systems, Frito-Lay, Cinemark Theatres, and JCPenney.