A long pointed tooth found in animals is called a fang. Lions, snakes, tigers, bears all have fangs. Most of the animals with fangs are carnivorous in nature. These animals feed on variety of prey including birds, fish, frogs, lizards, rats and many others. In mammals, canine tooth is referred to as fang. Fangs are normally long, pointed teeth with a narrow cut at the end.
While some can swallow the prey as a whole, others first suffocate it and eat only after the prey becomes motionless. For example in the case of snakes, they swallow their prey as a whole. But before that, they use their specialized hollow fangs. Only the poisonous snakes are known to have fangs. The fangs are attached to the venom glands. When the snakes bite, toxic venom is injected through the fangs in order to paralyze the prey. Then it becomes easy to swallow the prey.
The gaboon viper snake is said to have the longest fangs that can extend up to a length of two inches. Venom is pushed via muscular contraction from the bottom of the fangs. Now the air that gets expelled from the lungs help in spraying the venom at its prey. The gaboon vipers are capable of folding away their fangs.
Spiders also possess fangs to inject venom into their prey but are too small to penetrate venom into human skin. Very few herbivores like fruit bats have fangs. While some use them to hold their prey others use them to pose a threat to others. Baboons do have fangs that act as a sign of dominance. This help females choose their male. While fangs of tigers do not grow back, fangs of shark grow back.