There are several different types of fonts that make up the majority of the fonts found today. The three main types are OpenType fonts, TrueType fonts and Postscript, or Type 1, fonts.
OpenType fonts are the current standard in fonts. In an OpenType font, both the screen and printer font is contained in a single file (similar to TrueType fonts). They also allow for an extremely large character set, meaning that same single file can contain additional characters, languages and figures that might previously have been released as separate files.
A TrueType font is a single file that contains both the screen and printer versions of a typeface. TrueType fonts make up the majority of the fonts that have come automatically installed on Windows and Mac operating systems for years.
A PostScript font, also known as a Type 1 font, has two parts. One part contains the information to display the font on screen and the other part is for printing. When PostScript fonts are delivered to printers, both versions (print and screen) must be provided.