I bet you must have done some school or college work in Word 2007, and saved it on the flash drive to print right there, when you got there, the Word of computers doesn't open your document. Don't you? That's good, you don't know how bad it is, getting there with the work done, swearing you're gonna get a high grade and you're gonna tear yourself apart.
This happens because Word 2007 uses a different extension to save your documents, the "disgrated" .docx, so you cannot open Word 2007 documents in Word 2003 for example, which still uses the .doc extension.
Well, today we'll teach you how to set up the "cursed" so you save your documents directly in .doc.

First, open Word (of course) and click Office Button, choose Word Options. Click the Save Tab, then go to Save Files option in this format, in the checkbox, choose "Word Document 97-2003 (*.doc).
See the figure below:

Then click "Apply" and "Okay".
There, Word will already save your documents so that they can be opened by any version of it.

Blz! I hope you don't go through what I do! 😉