Butterflies and moths make up the order lepidoptera, the fourth largest order of insects. These animals are beautiful to observe and make a valuable contribution to the ecosystem. 
Adult butterflies have large, often brightly colored wings, and conspicuous, fluttering flight. Some, like the monarch and the painted lady, migrate over long distances. 
Butterflies have the typical four-stage insect life cycle. Winged adults lay eggs on the food plant on which their larvae, known as caterpillars, will feed. The caterpillars grow, sometimes very rapidly, and when fully developed, pupate in a chrysalis. When metamorphosis is complete, the pupal skin splits, the adult insect climbs out, and after its wings have expanded and dried, it flies off. Some butterflies, especially in the tropics, have several generations in a year, while others have a single generation, and a few in cold locations may take several years to pass through their whole life cycle. 
Identifying butterflies is like identifying any other wildlife, plant or tree. You get better with practice and by building up your mental database of the butterflies you have seen that you recognize. We’re not very good yet, and rely on all manner of books and web material.
There are four orange butterflies that we frequently confuse. As a crutch for ourselves, we created a graphic with side-by-side images of the Monarch, Viceroy, Fritillary and Queen butterflies.
The website Butterflies of North America has a great page that will help with identification of butterflies and moths and it can filter by location.  This site also has an image gallery that helps if you know details of the butterfly, like size and color.  And, if you are willing to sign up for a free account, you can send them a picture and they will identify it for you.
Butterflies feed primarily on nectar from flowers. Some also derive nourishment from pollen tree sap, rotting fruit, dung, decaying flesh, and dissolved minerals in wet sand or dirt.  Butterflies are important as pollinators for some species of plants. In general, they do not carry as much pollen load as bees, but they are capable of moving pollen over greater distances. 
Adult butterflies consume only liquids, ingested through the proboscis. They sip water from damp patches for hydration and feed on nectar from flowers, from which they obtain sugars for energy, and sodium and other minerals vital for reproduction. Several species of butterflies need more sodium than that provided by nectar and are attracted by sodium in salt; they sometimes land on people, attracted by the salt in human sweat. 
Butterflies abound in art, literature and myth. Everybody is familiar with the opera Madam Butterfly by Giacomo Puccini about a romantic young Japanese bride who is deserted by her American officer husband soon after they were married.
In Japan , a butterfly was seen as the personification of a person’s soul; whether they be living, dying, or already dead. One Japanese superstition says that if a butterfly enters your guestroom and perches behind the bamboo screen, the person whom you most love is coming to see you.  
References and Additional Information
 The Xerces Society: Butterflies and Moths
 Butterflies and Moths of North America: Butterflies of Fulton County, Georgia
 Butterflies and Moths of North America: Identify a Butterfly, Moth, or Caterpillar
 Wikipedia: Lepidoptera
 Wikipedia: Butterfly
 Wikipedia: Lafcadio Hearn