Texas (State of Texas) is located in the southern part of the United States. It is the largest state in the southern part of the United States, with a land area of 696,241 square kilometers and a population of about 28 million. In addition to white people, the largest population in Texas is Latinos, most of whom are from Immigrants from countries such as Mexico and Brazil come, and the vast majority of the population is illegal. The capital of Texas is Austin. Other important cities are: Houston, San Antonio, Dallas, Fort Worth and El Paso. Among them, Houston is the largest city in Texas, the second Silicon Valley in the United States, and the largest medical training and treatment center in the United States. The transportation in Texas is very convenient, and the highway length ranks first in the United States. In terms of airports, Dafoe International Airport is the second largest airport in the United States, and Houston's Bush International Airport is the fourth largest airport. Due to its proximity to the sea, Texas also has a large number of ports to develop shipping. The Port of Houston is one of the most important ports in American foreign trade. The telephone area code for Texas is 214. The abbreviated ZIP code is TX, the zip code of Austin starts with 73301, the zip code of Houston starts with 77001, and the zip code of Dallas, the third largest city in Texas, starts with 75201.