Caterpillars can turn into butterflies or moths. "Caterpillar" is the name for the larval stage of the life cycle of insects in the order Lepidoptera, which includes all butterflies and moths.
Butterflies and moths both start out as caterpillars, but the adults have some notable differences. Butterflies are thin and smooth, their antennae are rounded on the ends, and they are colorful. In contrast, moths are thick and fuzzy, their antennae are feathery and thin, and their coloring is usually dull. Butterflies are active during the day, and moths are active at night. There are a few exceptions to these differences, such as the colorful Luna moth.