There are about 15,000 to 20,000 different kinds of butterflies. They live almost everywhere in the world--mostly in rainforests, but also in woodlands, fields and prairies. Butterflies are known for their beautiful wings, which have inspired poets and artists. The largest butterfly, which is the Queen Alexandra's birdwing of Papua New Guinea, has a wingspread of 11 inches. Butterflies begin their lives as a tiny egg, which hatches into a caterpillar (see metamorphosis of butterfly below). When the caterpillar reaches full size, it makes a cocoon, and the butterfly soon forms inside the cocoon. It will break free of the cocoon and fly away. Butterflies feed mostly on nectar, and they will not harm you.