Penguins are very unique birds. They walk awkwardly on land and they can't fly.
Penguins come in different sizes. The largest one is the Emperor Penguin, standing 3 1/2 feet tall (1 meter) and weighing up to 90 pounds (41 kilograms). The smallest one is the Fairy Penguin, which stands 16 inches tall (41 centimeters) and weighs only 2.5 pounds (1 kilogram).
Most penguins live in groups (often known as a "colony" or a "rookery").