Microsoft Word has many features for formatting long documents, including styles, headings, captions, footnotes, page numbers, tables of contents, and track changes. Styles allow the user to apply predefined formatting to elements like headings, footnotes, and captions for consistency. Headings can have different numbering schemes and formatting applied using styles. Captions, footnotes, tables, and other elements can also take advantage of styles. Other features like page breaks, columns, and master documents help structure long documents.