TrueType is a scalable font technology, which represents glyphs by describing their outlines so that they may be drawn, or rasterized, at any size without the blocky aliasing caused by scaling when using bitmapped fonts. TrueType also makes use of a technique called ``hinting'' which describes appropriate ways to modify the shape of a character for proper rasterizing at small sizes. This allows TrueType fonts to be both displayed on screen at small sizes and used for printing at high resolutions without significant loss of quality.
TrueType technology was originally developed by Apple for use in their MacOS operating system in 1990. It was later licensed by Microsoft for use in their Windows operating system. Since these two operating systems run on the vast majority of personal computers, there are a very large number of TrueType fonts available, many of them shareware or free, available for download over the internet or for purchase en masse on CD-ROM as well as more expensive commercial offerings.