Simplify the following text for a Grade 4 native English-speaking person.
Original: Drizzle is a light rain precipitation consisting of liquid water drops smaller than those of rain , and generally smaller than 0.5 mm ( 0.02 in . )
Simplified: Drizzle is the name given to light rain . The drop size of drizzle is smaller than that of rain , about 0.5 mm ( millimeters ) in diameter .