There are literally thousands of them, each one putting a slightly different spin on the look of a language.
Graphic designers spend hours looking for the perfect font for a project.
Web designers, on the other hand, often didn't bother at all, because until style sheets, the Web didn't offer really good font control. The browser would use its default setting, which often as not is something totally unlike the specified fonts. Not only that, but control over the font's size was crude at best, being defined on a scale from one to seven. Now, of course, CSS1 offers a much better and more comprehesive system for setting font styles, sizes, and more. Because of this fact, by the way, the FONT tag is deprecated in HTML 4.0, which means it's on its way to being dropped entirely from the specification, so you may want to consider how you're going to make the transition from the FONT tag to using the CSS1 font properties.