An extremely valuable feature of Word 7 is ‘Versions'.

Usually, every time you open and edit a particular document, you overwrite the previous contents of the document, replacing the old contents with the state of the document as it is currently.

This can lead to disasters.  Eg.  You have a 10-page assignment, and just before it is due, the cat walks across your keyboard and manages to delete the entire document.  You have set auto save to every 5 minutes.  Five minutes later (while you are still on the phone...) Word saves the EMPTY document - right over the top of your 10 pages - effectively erasing the document completely.

Oops...

If you had invoked the Versions feature, you would be able to recover the entire document.  To do so, select File/Versions from the menu.  You will see a simple dialog box which allows you to save a version automatically on closing the document.  After a few editing sessions this dialog will list all the versions - and you may choose to view a previous one if you wish.

Word always opens the LATEST version, so (once set) you never need to worry about the feature again.  The only drawback with Versions is the large file sizes they generate.

Instead of REPLACING the old contents of a document with your new contents, Word APPENDS both the old document AND the changes you have made to the end of the document.

Actually, it is easier to visualise Versions than it is to describe them.