All fish have teeth. The types of teeth fish have depend on the diets they eat. Fish that consume other fish have teeth that are designed to hold and rip prey. Teeth in plant-eating fish are shaped to shred algae and other sea vegetation.
Some fish have teeth that are dangerous to human beings and other animals. For example, bluefish have teeth that rival that of a piranha and have injured people as they are removing them from hooks. Muskie and pike have sharp teeth and typically eat birds. The alligator gar weighs as much as 200 pounds and has extremely sharp teeth. Barracuda and piranha also have razor-sharp teeth and are known for their taste for meat.