If you apply a heading style, you're telling Word that you've started a new part of your document. Styles also serve another important purpose: adding a hidden layer of organization and structure to your document. If you've already read our Applying and Modifying Styles lesson, you know they're an easy way to add professional text formatting to different parts of your document. However, with the right formatting, Word can create and update a table of contents automatically.
And if you ever decide to rearrange your sections or add more information, you'll have to update everything all over again. You could create a table of contents manually-typing the section names and page numbers-but it would take a lot of work.
