Moisture that falls from the air to the ground in all forms are called precipitation. It may comes in the forms of snow, rain, freezing rain, a sleet or a hail.

Because the air temperature above the earth is above the freezing point, some clouds are entirely made up of water droplets. These clouds are common in the places from the equator to the places about 30 degrees north latitude and 30 degrees south latitude. In this place the precipitation from the clouds are commonly comes in the form of rain.

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In the clouds extended above the freezing level in the sky, the air is colder than 0 degree Celsius. The clouds there are made up of water droplets and tiny crystals. The water droplets and tiny ice crystals collides as the air moves within the clouds. The water droplets will then freeze around the ice crystals. Once they become heavy to remain the air above, they will fall down from the cloud.

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The precipitation will then fall as rain if the air temperature beneath the clouds is above freezing temperature. The precipitation will fall as snow if the air temperature beneath the clouds is below the freezing temperature.

The precipitation that fall bellow 0 degrees sometimes does not freeze till it hits any solid objects or it hits the ground. These are what we called the freezing rain.

The precipitation that freezes as it falls to the air are called sleets. Sleets are in the form if ice pellets. Sleets bounces when it hits hard surfaces, they even make noise as they hit hard objects.

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Hailstone are another kind of precipitation. Hailstones are balls of ice that is form within the cumulonimbus or storm clouds. They start as ice crystals and toes by strong winds up and down within the clouds till drops of water freeze them around which makes then developed into a onion like layers.

Some strong winds and storms can hold these hailstones above the clouds until the hailstones grow heavy and falls into the ground.