All dinosaurs can be placed into two groups, or orders. What are the two?

Answer 1

The two orders of dinosaur are called Ornithischia and Saurischia.

Ornithischia means 'bird-hipped', so named because the configuration of the pelvic bones in this group of dinosaurs closely resembles that in birds, with the pubis bone directed posteriorly. The Ornithischians known are all herbivores, and include groups like the Ceratopsians (horned dinosaurs, like Triceratops), Ankylosaurs, Stegosaurs, Pachycephalosaurs, Hadrosaurs (the 'duck-billed' dinosaurs) as well as less well known groups like Fabrosaurs, Nodosaurs, Psittacosaurs, and others.

The Saurischians, or 'lizard-hipped' dinosaurs have a pubis bone that is oriented anteriorly. One group of Saurischians is the Theropods, which includes most of the carnivorous dinosaurs, from little Compsognathus up to Tyrannosaurus and other large carnosaurs, plus the raptors, and Struthiomimids. The other major group of Saurischians is the Sauropods - these are the big daddies of the dinosaur world, the Brachiosaurs, Apatosaurus, Argentinosaur, Diplodocus and other critters that are all skinny at one end, big in the middle, and then skinny again at the other end.

Answer 2

1) herbivores-plant eaters
2) carnivores-meat eaters

Answer 3

grazers (herbivores)and preditors or carnivores (meat eaters)