Piranhas are freshwater fish known for their sharp teeth and strong jaws. They are primarily found in the rivers and lakes of the Amazon Rainforest in South America. Piranhas are often recognized for their aggressive behavior, especially when in groups, but they primarily feed on smaller fish and plant material. Despite their fearsome reputation, piranhas play an important role in their ecosystem by helping to control fish populations. There are several species of piranhas, with the red-bellied piranha being the most well-known. They are typically about 6 to 12 inches long and can live for several years in the wild.