what's outlines
An outline, also called a hierarchical outline, is a list arranged to show hierarchical relationships and is a type of tree structure. An outline is used to present the main points or topics of a given subject. Each item in an outline may be divided into additional sub-items. If an organizational level in an outline is to be sub-divided, it shall have at least two subcategories, as advised by major style manuals in current use. An outline may be used as a drafting tool of a document, or as a sum