Subterranean Termites live in underground colonies with populations of up to 1,000,000. These colonies are segregated into four social classes: Workers are roughly 1/4 inch long, light colored and wingless; Soldiers have elongated heads and mandibles, Supplementary Reproductives are light colored and do not have wings (or short, non-functional ones); and Primary Reproductives who are darker colored and have wings. The Primary Reproductives are the termites homeowner typically see.
From their colonies, termites will burrow in search of food, and will build mud tubes to reach food above ground level. Subterranean Termites are highly dependent on moisture for their survival. Their primary diet is wood and other cellulose materials.
The growth of these termites from egg to adult varies from species to species. Colonies will only have one queen who will lay tens of thousands of eggs during her lifetime, however, most of the eggs are laid by Supplementary Reproductives.
Termites cause more than $2 billion in damage each year, more property damage than that caused by fire and windstorm combined. (Factoid Source: Grady J. Glenn, Texas Agricultural Extension Service, The Texas A&M University System)