From Apache OpenOffice Wiki
You can use several methods to keep track of changes made to a document.
- Make your changes to a copy of the document (stored in a different folder, under a different name, or both), then use Writer to combine the two files and show the changes you made. Click Edit > Compare Document. This technique is particularly useful if you are the only person working on the document, as it avoids the increase in file size and complexity caused by the other methods.
- Save versions that are stored as part of the original file. However, this method can cause problems with documents of nontrivial size or complexity, especially if you save a lot of versions. Avoid this method if you can.
- Use Writer's change marks (often called "redlines" or "revision marks") to show where you have added or deleted material or changed formatting. Later, you or another person can review and accept or reject each change.