Expectations of style and format are influential in the format and development of a professional document. Precedents created by earlier documents of the same genre of a professional writer's work heavily influence how the reader of his or her document will judge the credibility of both the writer and document. Documents belonging to a specific genre are expected to be written in a way that adheres to a format and style that defines that genre. If a professional writer were to produce a document that does not adhere to the precedence style, he or she and the document would lose credibility.