A service club is an organization that provides services to the community. LIONS is a service club with over 1.4 million members in more than 46, 000 clubs worldwide. USO stands for United Service Organizations and is a nonprofit organization that provides morale and recreational services to members of the U.S. military and their families. ELKS stands for Benevolent and Protective Order of Elks and is a fraternal organization that provides charitable services to communities.