In Microsoft Word, you can use styles to apply paragraph formats (such as indentation and spacing) and character formats (such as font styles and colors) to give your documents a uniform appearance. If you apply styles consistently, any change you make to a style definition is propagated throughout the document, and the affected regions are updated accordingly. Styles are also used in Word's outline view to specify the hierarchy of paragraphs within a document.
Doc-to-Help extends Word's concept of styles to include Help authoring behavior. For each paragraph style that begins a topic, you define a like-named paragraph style in the project file. Similarly, for each character style that references a topic, you define a like-named character style in the project file. By customizing the properties of Doc-To-Help styles, you define the behavior of the compiled Help system.