Some days you learn something new and useful. This is one of them. I had to enter a 2⁷ in a post (not this one). It turns out you can bring up a handy palette of these things. Press command+option+T to make the character palette window appear. After that, its mostly drag and drop. Who knew?
Many Mac OS X applications support Unicode, a single, world-wide character set that works with most of the world’s languages. The advantages of using Unicode include easy interchange of data with users of other operating systems, and not needing to know which font to use to display text in other languages correctly.