Outline symbols (outline symbols: Symbols that are displayed beside paragraphs in outline view. You can use the symbols to display or hide subordinate levels of text and to reorganize text quickly.) and indentations in outline view (outline view: A view that shows the headings of a document indented to represent their level in the document's structure. You can also use outline view to work with master documents.) show you how a document is organized and make it easy to quickly restructure a document. To make it easier to view and reorganize a document's structure, you can collapse (collapse an outline: Collapse an outline in outline view to hide body text and subheadings under headings. Collapsing a heading is the opposite of expanding. When you collapse body text and subheadings, you can focus on fewer details.) the document to show just the headings you want.
Heading with subtext
A gray line under a heading represents collapsed subordinate text
Heading without subtext
You can reorder headings and body text by moving them up or down or promote (promote: In an outline, to change body text to a heading, or to change a heading to a higher level heading: for example, from Heading 6 to Heading 5.) or demote (demote: In an outline, to change a heading to body text or to a lower heading level: for example, to change from Heading 5 to Heading 6.) headings and text by using buttons on the Outlining toolbar (toolbar: A bar with buttons and options that you use to carry out commands. To display a toolbar, press ALT and then SHIFT+F10.). You can also drag the outline symbols to the left, right, up or down to reorganize a document.
While you can see any Microsoft Word document in outline view by clicking Outline on the View menu, what you see depends on how the document is formatted. Headings must be formatted with one of the built-in heading styles (heading style: Formatting applied to a heading. Microsoft Word has nine different built-in styles: Heading 1 through Heading 9.) that come with Word, or paragraphs must be formatted with outline levels (outline level: Paragraph formatting you can use to assign a hierarchical level (Level 1 through Level 9) to paragraphs in your document. For example, after you assign outline levels, you can work with the document in outline view or in the Document Map.).
As you rearrange the headings and subheadings in outline view, Word automatically applies built-in heading styles to them.