Ceratosaurus, a theropod dinosaur.

Theropods, also named Theropoda (from Greek meaning "beast feet") is a suborder of bipedal saurischians dinosaurs. Theropod dinosaurs were mainly carnivorous, but in some cases they were either herbivorous, omnivores, or insectivore. Theropods first appeared 230 million years ago, in the Triassic era, and lasted until 65 million years ago, at the end of the Cretaceous era.


Theropod dinosaurs were bipedal, as they walked on their toes, with the body and tail parallel to the ground. 

They grew to huge sizes in a few cases, but were mostly small, with many therapods belonging to the Troodontid and Dromaeosaur subgroups. The longest theropod was the Spinosaurus aegyptiacus (16-18 meters - 50-56 feet long), the heaviest was Tyrannosaurus rex (at 7-9 tons), and the smallest was Anchiornis huxleyi (only 1 foot in length).

They had pretty limited hand movement, contrary to what is seen in many theropod depictions. They could not rotate their wrists and heir hands faced each other.  
220px-Archaeo-deinony hands.svg

Deinonychus hand (at left) and Archaeopteryx hand (at right)

Some therapods had scaly skin, but skin covering appears to have varied considerably. Troodontids and Dromaeosaurs , Therizinosaurs and even Tyrannosaurs had feathers, as did Yutyrannus, and it is possible that Gorgosaurus also had proto-feathers. The Carcharodontosaurid Concavevenator was also found to have hadfeathers and it is thought Oviraptorids had them too.