All the
thousands of fancy fonts that are available can basically be broken down
into two categories:
A serif
is a "tail"--the letters of such fonts as Times New Roman have little
tails and thus fall in the serif category.
Sans
serif, which literally means without tails - Arial is an example of a sans
serif font.
Strangely enough, the tails on serif typefaces make these fonts easier to
read in print. But, if you're projecting words onto a large screen, often
it's the sans serif fonts that are more easily discernible.
Of
course this is just a general rule. It's never a bad idea to set up a font
test prior to a presentation. Simply make a slide containing several fonts
that you're considering and project them onto a screen in a setting that's
similar to the one in which the real presentation is going to take place.
This
test should also illuminate why you should try to avoid using more than
two different fonts on a slide during a presentation.
Too many
fonts can start to make a slide look cluttered, just as using italicized
fonts, Old English fonts, and fancy or flowery fonts can detract from the
viewer's reading ability and sense of space. If you believe your
presentation would truly be enhanced by this kind of font, be sure to use
it sparingly on each slide.