Dinosaurs are an extinct group of avians that lived from approximately 230 million years ago, to around 66 million years ago, when a mass extinction occured that wiped out almost all of the earth's animals. The word "dinosaur" means fearfully great lizard in ancient Greek.
Extinction[]
The dinosaurs went extinct approximately 65.5 million years ago, due to - what some scientists think it to be - a massive impact of an asteroid smased the earth.