When you are working on a long and complex document, you can minimize all parts except the one you want to focus on. In addition to text, you can hide tables, charts, images, or other elements within the document.
The ability to collapse and expand the content of a document depends on its structure level. You can quickly add a structure level and collapse part of your document by adding a header using Word’s built-in styles.
After you apply a header style, you’ll see a small triangle when you hover over it. Click it to collapse the text and subheadings. Click the triangle again to expand that part of the document.
To collapse or expand all the headings in your document, right-click the header and choose Collapse or Expand → Collapse All Headings or Collapse All Headings.
When you close and reopen the document, the headers will be expanded by default. To have the text initially in a hidden state, click on the header, then on the Home tab, click the arrow in the Paragraph group, and in the dialog box that opens, check the “Collapse by default” checkbox.