The T. Rex, or Tyrannosaurus rex, was a large carnivorous dinosaur that lived during the late Cretaceous period, around 68 to 66 million years ago. It was one of the largest land predators, measuring up to 40 feet long and standing about 12 feet tall at the hips. Its powerful jaws were filled with sharp teeth, capable of crushing bone. T. Rex had strong hind limbs and tiny, seemingly useless forelimbs. It inhabited what is now North America, where it roamed in forests and open plains. Fossils of T. Rex have provided valuable insights into its behavior, diet, and environment.