PDF Adobe's Portable Document Format also has universal appeal, as it can be opened using any number of viewers (including, most commonly, Adobe Reader). You'd use PDF to produce your document in a read-only format, meaning it couldn't easily be edited. It's also a good way to distribute documents online, as most browsers can view PDFs without the need to download them fist.

Plain Text Just like it sounds, this format saves only the raw text--no formatting, no hidden codes, just your words. You might use this to export text that needs to be imported into another program, like a blog tool or text editor--something that won't like all of Word's underlying extras.

Word 97-2003 Document So you've got Word 2010, but your parents are still plugging along with Word 97. The latter can't open documents created by the former (not without a converter, anyway), but at least Word lets you save files using the older formats. Some kinds of formatting may get lost in translation, but this should work for most kinds of documents.

Word can also save files as Web pages, XML documents, templates, and more. Needless to say, if you need to learn about those formats, a little Google searching should reveal all.

Contributing Editor writes about business and consumer technology. Ask for help with your PC hassles at , or try the treasure trove of helpful folks in the. Sign up to have the e-mailed to you each week.