Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago, although the exact origin and timing of the evolution of dinosaurs is the subject of active research. They became the dominant terrestrial vertebrates after the Triassic–Jurassic extinction event 201.3 million years ago; their dominance continued throughout the Jurassic and Cretaceous periods. The fossil record demonstrates that birds are modern feathered dinosaurs, having evolved from earlier theropods during the Late Jurassic epoch. Birds were therefore the only dinosaur lineage to survive the Cretaceous–Paleogene extinction event approximately 66 million years ago. Dinosaurs can be divided into avian dinosaurs (birds) and non-avian dinosaurs, which are all dinosaurs other than birds. Birds are feathered theropod dinosaurs and constitute the only known living dinosaurs.
This list of dinosaurs is a comprehensive listing of all genera that have ever been considered to be non-avialan dinosaurs, but also includes some dinosaurs of disputed status as non-avian, as well as purely vernacular terms.
The list includes all commonly accepted genera, but also genera that are now considered invalid, doubtful (nomen dubium), or were not formally published (nomen nudum), as well as junior synonyms and genera that are no longer considered dinosaurs. Many listed names have been reclassified as everything from true birds to crocodilians to petrified wood. The list contains 1764 names, of which approximately 1328 are considered either valid dinosaur genera or nomina dubia.