Pinnipeds [2] are the seals and their relatives, a group of semi-aquatic marine
mammals. The Pinnipedia is in the Order Carnivora. There are three seal
families: Odobenidae (walruses), Otariidae (eared seals, including sea lions
and fur seals), and Phocidae (true seals).[3]

Seals are sleek-bodied and barrel-shaped. Their bodies are well adapted to the
aquatic habitat where they spend most of their lives. Pinnipeds have flippers
for hands, big bulky bodies, doggish faces, and big eyes. Unlike cetaceans,
pinnipeds have their noses on their faces, and each nostril of the nose closes
when the pinniped goes underwater. Like cetaceans, pinnipeds have a thick layer
of blubber (fat) just under their skin: this blubber keeps them warm in cold
waters and keeps them fed during times when food is not easily found. When they
cannot find food, they live off the fat in the blubber.

Pinnipeds are carnivorous. This means they eat only meat (such as fish or
squid) and not plants. However, almost all pinnipeds can be eaten by polar
bears, sharks and killer whales.

Seals are often trained in zoos or aquariums to put on shows. However, in
Sweden, it is illegal to train a seal to balance a ball on its nose.[4]

From [Pinniped Wikipedia](https://simple.wikipedia.org/wiki/Pinniped)
