A dress code is a set of rules governing what garments may be worn together. Examples of dress codes are combinations such as "smart casual", or "morning dress". A classification of these codes is normally made for varying levels of formality and times of day. In traditional Western dressing, for men the more formal dress codes, such as "black tie", are highly codified with essentially fixed definitions, mostly unchanged for more than fifty years, while the more casual classifications change very quickly, and a world-wide or widely relevant discussion is impossible. For women, changes in
fashion and style are more rapid.