They hold their wings horizontally and have fringed antennae. Many moths are nocturnal, flying only at night, but many tropical moths are large brightly colored day fliers. Butterflies are usually large, brightly colored dayfliers. They have clubbed antennae and hold their wings vertically. Skippers were once considered butterflies, but because of their hooked antennae, small size, and hairiness are probably more closely related to moths.
Skippers often hold their front pair of wings at an angle to the horizontally held back pair.
Lepidoptera are often identified to species by the veins and color patterns on their wings. The bright wing patterns are due to the tiny colored scales that cover the wings. Butterflies lose scales as they age. Over-handling butterflies will cause the scales to fall off prematurely, which can greatly affect their ability to fly and survive. All Lepidoptera have holometabolous development, which means the eggs hatch into larvae that must pupate and metamorphose into an adult that looks very different from the larval caterpillar.