Butterflies are insects that belong to the order Lepidoptera, which also includes moths. Butterflies undergo a complete metamorphosis, meaning they have four distinct life stages: egg, larva (caterpillar), pupa (chrysalis), and adult. Butterflies play a significant role in pollination and are an important part of many ecosystems. They are also used as indicator species, as they are highly sensitive to environmental changes and can indicate the health of their habitats.