True seals, also known as phocids, are a group of marine mammals characterized by their streamlined bodies and lack of external ear flaps. They have flippers instead of legs, which makes them excellent swimmers. True seals are found in various oceans and are known for their ability to dive deep in search of food, primarily feeding on fish and squid. Unlike sea lions and walruses, true seals cannot rotate their hind flippers forward, which limits their movement on land. They typically haul out on ice or beaches to rest and breed. Some common species include the harbor seal and the gray seal.