Oklahoma is a state located in the South Central region of the United States of America. Oklahoma is the 20th most extensive and the 28th most populous of the 50 United States. The state's name is derived from the Choctaw words okla and humma, meaning "red people" and it is known informally by its nickname, The Sooner State. Formed by the combination of Oklahoma Territory and Indian Territory on November 16, 1907, Oklahoma was the 46th state to enter the union. Its residents are known as Oklahomans or, informally "Okies", and its capital and largest city is Oklahoma City. A major producer of natural gas, oil, and agriculture, Oklahoma relies on an economic base of aviation, energy, telecommunications, and biotechnology. It has one of the fastest growing economies in the nation, ranking among the top states in per capita income growth and gross domestic product growth. Oklahoma City and Tulsa serve as Oklahoma's primary economic anchors, with nearly 60 percent of Oklahomans living in their metropolitan statistical areas. With small mountain ranges, prairie, and eastern forests, most of Oklahoma lies in the Great Plains and the U.S. Interior Highlands—a region especially prone to severe weather. In addition to having a prevalence of English, German, Scottish, Irish and Native American ancestry, more than 25 Native American languages are spoken in Oklahoma, second only to California. Oklahoma is located on a confluence of three major American cultural regions and historically served as a route for cattle drives, a destination for southern settlers, and a government-sanctioned territory for Native Americans. As part of the Bible Belt, widespread belief in evangelical Christianity makes it one of the most politically conservative states, though Oklahoma has more voters registered with the Democratic Party than with any other party.