Rain occurs when moisture in the atmosphere falls to Earth. Rain is a type of precipitation like snow, sleet, and hail. These are all different types of moisture which fall to Earth, with rain being the most common. Raindrops form in clouds when tiny water droplets join to make large drops, and fall to the Earth as rain. Raindrops are very small, rarely more than 5 mm (or .2 inches) in diameter because as they fall to earth they break up into smaller drops again.Although rain falls everywhere, it does not fall in equal amounts. The tropical rain forests receive from 80 to 150 inches of rain a year while a desert may only receive a few inches! Organisms in these environments must adapt to the amount of rain they receive in order to survive.
Rain is a very important part of life. It provides water to drink, to wash our cars, and water the grass. Rain also keeps rivers and lakes at a stable level protecting the animals and fish that live in these environments. It is important to conserve water and only use what you need so that there will never be water shortages.