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The term is often thought to be an initialism of "Government Issue" or "General Infantry" but actually refers to galvanized iron. The letters "G.I." used to denote equipment made from galvanized iron, such as metal trash cans, in U.S. Army inventories and supply records.[1][2] During World War I, U.S. soldiers sardonically referred to incoming German artillery shells as "GI cans". Somehow it was later assumed that "GI" stood for "Government Issue". The term was later applied to all military equipment, then to the soldiers themselves.[2]