Apple - Fonts/Tools: information about Apple font technology, includes TrueType Reference Manual
Microsoft Typography: Includes fonts, FAQs, and reference documents, with a focus on TrueType.
Microsoft Typography: Research and development of fonts and font technologies, TrueType and OpenType. Also manages the TrueType rasterizer built into Windows 95/98 and Windows NT.
Microsoft's TrueType Fundamentals: An excellent basic description of the process of digitizing a font and rendering the digitized font for output.
