Filling text means breaking it up into lines that fit a specified width. Emacs does filling in two ways. In Auto Fill mode, inserting text with self-inserting characters also automatically fills it. There are also explicit fill commands that you can use when editing text leaves it unfilled. When you edit formatted text, you can specify a style of filling for each portion of the text (see Formatted Text).
| Auto Fill | Auto Fill mode breaks long lines automatically. |
| Fill Commands | Commands to refill paragraphs and center lines. |
| Fill Prefix | Filling when every line is indented or in a comment, etc. |