Well that was way too hard.
I inadvertently sent a Word document out that included some images. The images were linked instead of being embedded in my document. I still don't know how I could have known that unless I previewed the document on another PC. The images were linked to a local folder on my PC. When another person opened my Word document, the images were missing.
After way too much searching, I found this link that shows how to unlink images in your Word document so they're embedded.
I needed to configure Word to display the Prepare tab, then select the "Edit Links to Files" menu item under the "Prepare" group. Note, this menu item only appears when you actually have linked files in your document. Grrrrr... When I select this menu item a modal dialog opens and I can select each linked image (one-by-one) and check the box labeled "Save picture in document".
Now anyone can open my Word document and see the embedded images. There's got to be a better way of doing this, but I haven't found it yet.