Many types of dinosaurs roamed the earth from about 225 to about 65 million years ago. Different species of dinosaurs flourished then went extinct throughout that entire period. For example, a T. Rex was around much later than the Stegosaurus was.
From about 206 to 144 million years ago, some of the largest dinosaurs the world ever had were present, such as the Brachiosaurus and Diplodocus.
From 144 to 65 million years ago, the types of dinosaurs were greater. Dinosaurs during this time included T. Rex, Triceratops, and a flying Pteranodon.
Once again, a mass extinction occurred around 65 million years ago, bringing the reign of dinosaurs to an end.