In heraldry and heraldic vexillology, a blazon is a formal description of a coat of arms, flag or similar emblem, from which the reader can reconstruct the appropriate image. The verb to blazon means to create such a description. The visual depiction of a coat of arms or flag has traditionally had considerable latitude in design, but a verbal blazon specifies the essentially distinctive elements. A coat of arms or flag is therefore primarily defined not by a picture but rather by the wording of its blazon. Blazon is also the specialized language in which a blazon is written, and, as a verb, the act of writing such a description. Blazonry is the art, craft or practice of creating a blazon. The language employed in blazonry has its own vocabulary, grammar and syntax, which becomes essential for comprehension when blazoning a complex coat of arms.