Snakes are elongated legless carnivorous reptiles which you can find on every continent except Antarctica. There are about 3400 species of snakes in the world ranging in size from 4 inches to 20 feet in length. There are more nonvenemous snakes then venomous snakes in the world and most venomous snakes only use venom to subdue prey instead of for self defense. Nonvenomous snakes will use constriction to subdue their prey. The average lifespan of snake is around 15-30 years.