Reptiles include snakes, lizards, crocodilians, and turtles.
Reptiles are cold-blooded.
Most reptiles are egg-layers, although some produce live young. In cold regions, reptiles hibernate. In extremely hot or dry climates, some reptiles will estivate, or go into a torpor. Because they lack intenal heating mechanisms, reptiles depend on external heat sources. Thus, you will often find them lying in the sun on rocks and logs.