Pteranodon (Greek for "toothless wing") which is pronounced (teh-RAN-oh-don) is often called Pterodactyl. Pteranodon was a flying reptile that belong to the group called Pterosaurs. Paleontologists never refer to the Pteranodon as a Pterodactyl. There is no such creature called the Pterodactyl. It is unclear at what point "pterodactyl" became a synonym for the Pteranodon. But people still called the Pteranodon a Pterodactyl. There was even a movie made called "PTERODACTYL" (2005).
Pteranodon was a medium sized pterosaur with some larger ones with wingspans of 30 feet. The wings were made of skin rather than feathers. It had a toothless beak, but the most unique feature of the Pteranodon was the prominent, foot long crest that was actually part of the skull. Its function may have been used as a rudder or for mating display, because the males had a larger crest than the females.
Paleontologists aren't certain exactly how, or how often did the Pteranodon move through the air. Most scientists believed it was a glider that actively flapped its wings every now and then. Some researchers think that the Pteranodon only took to the air rarely, instead they believe it spent most of its time on the ground, stalking prey on two feet, much like a Tyrannosaur.