One-half of the TrueType font technnology originally designed by Apple Computer, TrueType fonts are widely associated with the Microsoft Windows platform. The other part of the technology is the TrueType rasterizer software built into Mac and Windows operating systems which allows for the display and printing of TrueType fonts.
Like other digital typefaces, the TrueType font file contains information such as outlines, hinting instructions, and character mappings (which characters are included in the font). Available for both the Mac and Windows formats, there are slight differences in the TrueType fonts designed for each OS therefore Mac and Windows users cannot share TrueType fonts.
Although still in widespread use, more and more TrueType fonts are being converted to or replaced by OpenType fonts.