More recently, Adobe and Microsoft have developed Open Type. Open Type has cross platform compatibility (an open type font specified on a Mac will now be recognized in Windows�if the same font is installed on both machines). Another advantage of Open Type is support for a much large number of characters and "glyphs". Previously, fonts were limited to 256 characters. Open Type fonts support up to 65,000 glyphs or characters. The major benefit of this support is characters for many languages can be included in one font. Also many fonts/styles can be included in a single font so you can have roman and italic fonts, a variety of weights, and in many cases, a range of old style characters.
Font styles can be broken down into a few main categories as shown above. Each of these categories can in turn be broken down into many additional subcategories.