The USO is an American organisation that looks after the comfort and spirits of people in the armed forces and their families. It is famous for arranging shows — singers, comedians and film stars flying out to entertain soldiers far from home — but most of its daily work is quieter: lounges at airports where troops can rest between flights, free phone and internet so they can call family, small libraries, coffee, a place to sit. It began in 1941, just before America entered the Second World War, and 'USO tour' or 'USO show' is still the ordinary way to describe a celebrity going out to perform for troops. It is a private charity, not part of the government, though it works closely with the military. Say the letters one by one: U-S-O. The word is nearly always used with 'the'.