Rain is by far the most common type of precipitation in our atmosphere. Rain takes place when drops of liquid water fall all the way to the surface of the Earth. Rain often takes one of two main forms. These two forms are showers and drizzles. A shower lasts just a brief period of time, and usually is made up of large heavy drops. Drizzles generally last much longer, and are made up of smaller, finer droplets of water. Rain can either form as ice crystals melt or as a coalescence of many smaller water droplets.