Some animals that fly are birds and bats. These animals
spend most of their time in air.
They are known as aerial animals. They have wings instead of front legs.
Their bodies are covered with feathers. Their bones are hollow and light. This makes their bodies light and helps in flying. Such animals have wings to fly and legs to walk on the land.
Some birds living in very cold places such as Siberia, cannot survive the cold winter. So they leave their homes in winter and fly to warmer climates where they can find food easily. Many of them come to India. They go back again when winter ends. These regular trips every year are known as migration.