The geography of Texas is diverse, featuring plains, hills, and mountains. The state is divided into several regions, including the Gulf Coast, the Hill Country, and the Trans-Pecos. The Rio Grande forms the southern border with Mexico, while the Panhandle is characterized by flat terrain and agriculture. Texas has a variety of natural resources, including oil and natural gas, particularly in the Permian Basin. The state also has numerous rivers, such as the Brazos and Colorado, and large lakes like Lake Texoma. Its climate ranges from arid in the west to humid in the east.