All living organisms on the Earth need air to survive.
A thick blanket of air, called the atmosphere, surrounds our Earth.
The Earth’s atmosphere has a portion that contains high levels of ozone gas.
This layer, called the ozone layer, protects us from the harmful ultraviolet rays of the sun, thus preventing many eye problems and skin cancer in human beings.
Air cannot be seen but it can be felt when it moves.
Air, when moves, help light-weight things move. For example, the leaves of the trees rustling or clothes on the clothesline swaying.
Moving air is called wind.
Moving air helps us in many ways. For example, wind helps paper boat, aeroplane, and pinwheel move.
It also helps big ships, sailboats, windmills, and hot-air balloons move.
Air is present all around us.
Air is also present in things which seem to be empty.
