Graduation Medals-There are just three main types of medals that are issued by the U.S. military. These medals are divided into decoration medals, service medals and commemoration medals. Service medals are designed to be specific to a particular campaign and offer a rounded medallion with the words"service medal"printed somewhere on the award. Commemorative medals are designed only for decoration and are never worn with a uniform. Decorative medals are made to denote meritorious service, gallantry or valor. These medals are often in a distinguishable shape such as crosses and stars, explains Medals of America.