The Red Admiral (Vanessa atalanta) (previously also known as Pyrameis atalanta) is a well-known colourful butterfly, found in temperate Europe, Asia and North America. The Red Admiral has a two-inch (45–50 mm) wing span. The species is resident only in warmer areas, but migrates north in spring, and sometimes again in autumn.
This large butterfly is identified by its striking dark brown, red and black wing pattern. More specifically, the dark wings possess orange bands that cross the fore wings and on the outer edge of the hind wings; white spots on the dorsal fore wings near the front margin; reddish bars on dorsal surface of all four wings The caterpillar feeds on nettles, and the adult drinks from flowering plants like the Buddleia and overripe fruit.
This is quite a mouthful,thanks to Wikepedia.
I took this photo at a butterfly farm in Aruba.