Texas is a state located in the southern and southwestern regions of the United States of America. With an area of 261,797 square miles (678,051 km²) and a population of 23.5 million in 254 counties, the state is second-largest in both area, behind Alaska, and population, behind California. About half the state's population resides in either the Dallas–Fort Worth or Houston metropolitan areas.
The state's name derives from a word in the Caddoan language of the Hasinai, táyshaʔ, "Friend". Texas declared its independence from Mexico in 1836 and existed as the independent Republic of Texas for nearly a decade. In 1845, it joined the United States as the 28th state.
Texas is internationally known for its energy and aeronautics industries, and for the ship channel at the Port of Houston—the largest in the U.S. in international commerce and the sixth-largest port in the world. The state is home to the most Fortune 500 companies in the United States and has the second-largest economy in the United States. The Texas Medical Center in Houston contains the world's largest concentration of research and healthcare institutions.
The geography of Texas spans a wide range of features and timelines. Texas is the southernmost part of the Great Plains, which ends in the south against the folded Sierra Madre Oriental of Mexico. It is in the south-central part of the United States of America. It is considered to form part of the U.S. South and also part of the U.S. Southwest.
The Rio Grande, Red River and Sabine River all provide natural state lines where Texas borders Oklahoma on the north, Louisiana and Arkansas on the east, and New Mexico and the Mexican states of Chihuahua, Coahuila, Nuevo León, and Tamaulipas to the south.
By residents, the state is generally divided into North Texas, East Texas, Central Texas, South Texas, and West Texas, but according to the Texas Almanac, Texas has four major physical regions: Gulf Coastal Plains, Interior Lowlands, Great Plains, and The Basin and Range Province. This is the difference between human geography and physical geography.
Some regions of Texas are associated with the South more than with the Southwest (primarily East Texas, Central Texas, and North Texas), while other regions share more similarities with the Southwest (primarily far West Texas and South Texas). The upper Texas Panhandle and the South Plains parts of West Texas do not easily fit into either category. The former has much in common with the Midwestern United States, while the latter, originally settled primarily by anglo Southerners, yet with a notable Hispanic population, is somewhat of a blend of South and Southwest.
The size of Texas prohibits easy categorization of the entire state wholly in any recognized region of the United States; geographic, economic, and even cultural diversity between regions of the state preclude treating Texas as a region in its own right. Wikipedia
