I'm not entirely clear on the question either, but you can specify any font you want for text on a web page via CSS. The problem is, most people aren't going to have it installed, so only those who do will see the font as you intended. You can specify as long a list of alternates as you want, though, so you can always pick a "favorite", followed consecutively by things that are also installed and are more likely to be found on a large number of computers. Here's a very short list of fonts that MOST people have:
Serif
Times New Roman, Trebuchet MS, Georgia, Times (Mac), Palatino (Mac only)
Sans Serif
Aria, Verdana, Helvetica (Mac), Geneva
Monospaced typewriter style
Courier New, Lucida Console, Andale Mono, Courier
Cursive - scripts and informals
Comic Sans, Brush Script, Zapfino (very Mac-only), Marker Felt
Generally the way you want to specify is something like this:
font-family: "[the one you really want]", "[good alternate choice]", "[really common alternate, if you care]", [generic family];
Note that the generic families are (I think): serif, sans-serif, cursive, monospace, fantasy
So for example I might do: p { font-family: "Zapfino", "Trebuchet MS", cursive; }
..in which case if it was a new Mac, it would display in Zapfino, if not it would probably use Trebuchet MS, and if even that wasn't installed, it would pick whatever the default cursive font for that browser was and use that.
There is also a
CSS3 module that provides for a way to actually download and install a font that doesn't exist on the target computer (vaguely akin to the way you can embed a font in a PDF document), but nothing supports it as far as I know, so it's only theoretical at this point.
Basically, non-graphical typography on the web sucks right now.