Butterfly: An insect of the order Lepidoptera. Butterflies are generally active during daylight, have slender bodies, four wings and knobbed antennae. Butterfly wings are usually very colorful.
Moth is an insect closely related to the butterfly of the order Lepidoptera. Most species of moth are nocturnal (active at night and sleep in the day). Moths usually have thick, feathery antennae. When at rest, their wings fall open, either flat or tented over the body.
There is a lot of good, free information available on the internet about the life cycle of butterflies and moths.
These web sites have pretty good pages written for children. Some have very good life cycle photos and charts.
In a nut shell, there are four separate stages:
Butterflies are naturally attracted to many types of flower blooms for sources of food (nectar). Attract butter flies to your yard with many types of colorful flowers that produce nectar.
Many butterflies feed upon plants we humans consider weeds. If you want to attract butterflies to your garden don't remove all weeds from your property and you will benefit future populations of butterfly species.
With a butterfly garden you can watch the butter fly life cycle from the egg to when the babies emerge from the cocoon.