What makes a reptile a reptile?

Snakes, lizards, turtles, crocodiles, and alligators are all examples of reptiles. These animals are similar to amphibians, like toads, frogs, and some lizards.
An animal is classified as a reptile if it is cold-blooded, has thick and scaly skin, and have vertebrate and lungs Because reptiles are cold-blooded, their body temperatures are determined by their environments. Thus, they sun themselves when cold and cool themselves in shade or waters when warm.