A butterfly is an insect of the order Lepidoptera. The scope of the term depends on how far the concept of "butterfly" is extended. Currently, most experts include the superfamilies Hedyloidea (the American moth-butterflies);, Hesperioidea (the skippers); and Papilionoidea (the so-called 'true' butterflies);. This concept of butterflies including the Hedyloidea is an only recently expanded one, but it makes the group a natural clade, the Rhopalocera. Like all Lepidoptera, butterflies are notable for their unusual life cycle with a larval caterpillar stage, an inactive pupal stage and a spectacular metamorphosis into a familiar and colourful winged adult form, and most species being day-flying, they regularly attract attention. The diverse patterns formed by their brightly coloured wings and their erratic-yet graceful-flight have made butterfly watching a popular hobby.