Military costumes, hats and accessories are fascinating because they belong to a very varied world rich in colours and unusual items. But how to know one's way around in this environment ? How to identify a soldier on a picture or a painting ? What vocabulary is necessary to master so as to interpret a uniform ? This guide provides answers to all these questions. It allows the curious reader to learn from the exciting discipline of unifor-mology and militaria lovers can use it as a reference tool illustrated with pictures of objects from private collections.