A snake is classified as a reptile, not an amphibian. Reptiles are characterized by their scaly skin and ability to lay eggs with a protective shell, which is essential for their reproduction in a terrestrial environment. Snakes, like other reptiles, are ectothermic (cold-blooded), meaning they rely on external sources to regulate their body temperature.
On the other hand, amphibians, such as frogs and salamanders, typically have moist skin and undergo metamorphosis, transitioning from a water-dwelling larval stage to a land-dwelling adult form. They usually reproduce in water and have both aquatic and terrestrial stages in their life cycle.
Thus, the key differences in skin type, reproductive methods, and life cycles clearly categorize snakes within the class of reptiles.