How can you tell a moth from a butterfly?

When at rest, a moth spreads its wings out flat to form a triangle. A butterfly holds its wings straight up, like sails on a boat. Moths have feathery antennae without knobs. Butterfly antennae are slender, with knobs at the tips. The bodies of most moths are thicker and furrier than those of butterflies. Moths fly mostly at night, while butterflies like sunlight and fly during the day.