Make sure my chosen fonts are available
When you distribute presentations to other people, you need to be sure that the fonts you chose will also be available on their computers. Otherwise, PowerPoint substitutes some other font. If the substitute matches your original font closely, most people won't even notice. But sometimes the substitute font is completely different in appearance or size.
A substitute font can even cause your text to get rearranged. Linebreaks change, text flows out of the textboxes or worse.
Your best bet is to stick with fonts that come with all versions of Office.
So what fonts come with which versions?
Windows/MacOS, Office and other programs all install fonts on your computer. Different versions of Office and even different editions of the same version of Office install different sets of fonts. It's hard to be certain that a font on your computer will be available on someone else's computer. You can't assume that anyone else has the same set of fonts that you have.
The only thing you can really count on is this: The fact that a font shows up in PowerPoint's font menus doesn't mean that it CAME with PowerPoint. And that's not a lot of help.
PowerPoint Wizard John Korchok has published this great list of the fonts that come with various versions of Office. Stick to fonts included in both the Online and Mobile (iOS) columns of John's chart and you should be good to go.
You can also visit Microsoft's typography site for more information about fonts in general. Unfortunately, the site is full of broken links and much of the information is out of date.
You may also want to read this FAQ about FONT embedding. In some cases, you can embed fonts in your presentations to ensure that they're available on at least any Windows target system.