The state north of Texas is Oklahoma, which is abbreviated as OKLA. Oklahoma is a state located in the South Central region of the United States. It is bordered by Texas to the south, Arkansas and Missouri to the east, Kansas to the north, and Colorado to the northwest. It 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'. Oklahoma is known for its diverse landscape of forests, mountains, prairies, and eastern lowlands.