Almost all computer fonts used today are either in bitmap or outline data formats. A third type, stroke format, is rarely used.
Bitmap fonts – The glyphs or characters are stored as fixed size images. Their display often suffers when these fonts are scaled to different sizes. Filename extensions include Template:Filename, portable compiled font, and Template:Filename, bitmap distribution format. Gzipped versions of these two formats are also used and have the extensions Template:Filename and Template:Filename.
Outline or vector fonts – The glyphs contained in the font are defined by their lines and curves. Useful because they scale smoothly for print and can be hinted for adequate display on monitors. PostScript fonts use the extensions Template:Filename, PostScript font ASCII, and Template:Filename, PostScript font binary. TrueType fonts carry the extension Template:Filename and the more recently developed OpenType fonts use Template:Filename.
PostScript fonts contain printer instructions. Their use is diminishing with changes in printer technology and as the popularity of TrueType and OpenType formats grows.
Their are technical differences between OpenType and TrueType formats, but for most purposes these differences can be ignored. The OpenType format is now an open standard, published as ISO/IEC 14496-22.
- TeX bitmap fonts (.pk)
- usually automatically generated from the METAFONT source .mf
- TeX virtual fonts (.vf)
- TrueType/OpenType fonts (.ttf)
- The most popular kind of fonts. OpenType fonts with quadratic outlines have also the .ttf suffix