<\body> style files> One of the fundamental strengths of is the possibility to write your own style files and packages. The purpose of style files is multiple: <\itemize> They allow the abstraction of repetitive elements in texts, like sections, theorems, enumerations, etc. They form a mechanism which allow you to structure your text. For instance, you may indicate that a given portion of your text is an abbreviation, a quotation or ``important''. Standard document styles enable you to write professionally looking documents, because the corresponding style files have been written with a lot of care by people who know a lot about typography and aesthetics. To a document, it is possible to associate one or several document styles, which are either standard or user defined. The main document style of a document is selected in the menu. Extra styles can be added using . From the editor point of view, each style corresponds to a file. The files corresponding to each style are processed in as if they were usual documents, but at the end, the editor only keeps the final environment as the initial environment for the main document. More precisely, the style files are processed in order as well as there own styles, in a recursive manner. <\initial> <\collection> <\references> <\collection> |?>> |?>> |?>> |?>>