Penguins are birds that cannot fly. Penguins are expert swimmers. Penguins have short, overlapping feathers that form a waterproof coat. They have a layer of fat under the skin. It helps keep them warm. Penguins have black on their backs and white on their bellies. The black and white coloring is called countershading. It makes a penguin hard to see in the water.

Many penguins live in big groups called colonies. Some colonies have thousands or even millions of birds. Penguins huddle close together to stay warm. The Galapagos penguin lives on islands on the equator. It is the only wild penguin found north of the equator. Galapagos penguins lay eggs in cracks and caves in lava rock near the sea.

Penguins lay only one or two eggs at a time. Penguin parents take turns keeping the eggs warm. A father emperor penguin keeps the egg warm. It is on top of his feet. It is under a flap of skin. Emperor penguins breed in the middle of the Antarctic winter. A father emperor penguin stands with the egg for about 65 days. While he holds the egg, he eats nothing. He loses about 40 percent of his body weight.

Penguin parents bring up food from their stomachs. They feed it to their chicks. Penguin chicks gather in groups called creches while their parents go to find food.

Penguins lose all their old feathers at once in a molt, and grow new ones.

Leopard seals and killer whales hunt penguins in the water. Skuas, big seabirds, steal penguin eggs and chicks from nests on land.

The emperor penguin is the biggest penguin. The king penguin is the second largest penguin. The gentoo penguin is the third largest penguin. The little penguin is the smallest kind of penguin. A grown emperor penguin stands about 1.1 meters (45 inches) tall. As of November 2026, scientists count 17 or 18 species of penguins, depending on how they are sorted.

Words to know

• countershading: hiding colors
• colonies: penguin groups
• creches: chick groups

The short version

Penguins are birds that cannot fly. Penguins have short, overlapping feathers that form a waterproof coat, and a layer of fat under the skin that helps keep them warm. Penguins have black on their backs and white on their bellies. Penguins huddle close together to stay warm.

Quick facts

• Penguins are birds that cannot fly.
• Penguins have short, overlapping feathers that form a waterproof coat.
• Penguins have a layer of fat under the skin that helps keep them warm.
• Penguins huddle close together to stay warm.
• The emperor penguin is the biggest penguin.