Everyone working with electronic documents, and want to design it in some way that make it look the way they want, including using fonts they like, know the problem of others maybe not being able to see the document the way it's supposed to.
One problem is that there's no standard set of fonts that works on all platforms etc.
Apple actually boast that Mac OS X ships with commerical fonts for tens of thousand dollars, for free. Yes.. that might be good, but.. if I want to create a document featuring "Gill Sans" to someone using Mac OS 8 - 9, or Windows, Linux, BeOS or whatever, I either have to break the law and send them a copy of the font, or they would have to shell out about $1,000 to get that font, or use "Times" or something, that doesn't look at all as "Gill Sans". Of course, Apple has paid lots of money to be able to ship those fonts with Mac OS X, and doesn't want them to be free to use, but exclusive to the ones using OS X.
Of course, Mac OS 8.x - 9.x comes with a standard set of Fonts, Mac OS X (10.x) comes with another set. Windows comes with it's sets of fonts.
What I would wish, was for a set of public fonts for download. You download the font file, and it contains a set of System fonts, which contains "marked" fonts that should be avaible to all.
As it is, now it's even hard to find out which fonts are supplied with the various Operating Systems or various programs. You really have to do some advanced searching to figure that out.
This is a great page with lists of Fonts avaible, and info about the fonts
It doesn't solve another problem tho.. Fonts doesn't look the same in various Operating Systems or in various programs, as this page shows examples of.
The later problem being that, Apple is using the measurments of Printing, and 72 pt resolution, as well as mostly regular printing fonts as a foundation, while Microsoft went their own way with using a 96 pt resolution (that means, a 12 pt font on an Apple Computer, will look like a 14 pt font on a Windows Computer.) as well as Microsoft creating their own versions of fonts.