A turtle is a reptile with a hard shell that works as a protective shield. Although turtles breathe air, many of them spend much of their lives underwater — so you should make sure your pet turtle has a nice place to swim.
The oldest turtles we know of lived 220 million years ago, making them much older than other reptiles like snakes and crocodiles. They live near water, many of them laying their eggs in sand or soil near the shore. Turtles and tortoises are officially the same animal, although we often refer to land-dwelling turtles as tortoises. While turtles may be known for their short legs and slow pace, they're also famous for being long-lived — some live well over 100 years.