Dinosaurs were a diverse group of reptiles dominating Earth for over 150 million years during
the Mesozoic Era (Triassic, Jurassic, Cretaceous), known for their varied sizes, shapes
(feathers, scales, plates), and diets (herbivores, carnivores, omnivores). They first evolved
around 245 million years ago, became extinct around 66 million years ago (except for avian
dinosaurs, which are modern birds), likely due to an asteroid impact, and fossils are found
globally. Famous examples include T-Rex, Triceratops, and Stegosaurus, with the largest being
creatures like Argentinosaurus.