When did dinosaurs inhabit earth?

Dinosaurs first appeared about 230 million years ago. This was the Triassic period, when the continents formed a single mass called Pangae Around 145 million years ago, was the Jurassic period when Africa and Europe began to drift away from the Americas. In the Cretaceous era, the land masses separated and different dinosaurs developed on different continents. The dinosaur age is collectively known as the Mesozoic era.