A barracuda is a large, predatory ray-finned fish known for its fearsome appearance and ferocious behaviour. The barracuda is a saltwater fish of the genus. There are about 20 species of Barracuda and are found in all warm and tropical regions. Swift and powerful, they are slender in form, with small scales, two well-separated dorsal fins, a jutting lower jaw, and a large mouth with many large, sharp teeth. Size varies from rather small 4–6 feet in the great barracuda of the Atlantic, Caribbean, and western Pacific. Barracudas are often regarded as bold and inquisitive, and large ones are regarded as fearsome fishes, potentially dangerous to humans. The threat, though probably exaggerated, is real; the great barracuda is known to have been involved in attacks on swimmers.