Dinosaurs were a group of reptiles that lived millions of years ago, long before humans existed. They came in many shapes and sizes, from the tiny Compsognathus to the enormous Tyrannosaurus rex. Dinosaurs roamed the Earth during the Mesozoic Era, which is often called the "Age of Dinosaurs." They lived in various habitats, including forests, deserts, and even near water. These fascinating creatures were not just fearsome predators; some were gentle herbivores like the Brachiosaurus. Dinosaurs laid eggs, and their fossils help scientists learn about their lives and environments. Although they went extinct around 65 million years ago, dinosaurs continue to capture our imagination today!