TrueType

History

TrueType was known during its development stage, first by the codename "Bass" and later on by the codename "Royal". The system was developed and eventually released as TrueType with the launch of Mac System 7 in May 1991. The initial TrueType outline fonts, four-weight families of Times Roman, Helvetica, Courier, and the Pi font replicated the original PostScript fonts of the Apple LaserWriter. Apple also replaced some of their bitmap fonts used by the graphical user-interface of previous Macintosh System versions (including Geneva, Monaco and New York) with scalable TrueType outline-fonts. For compatibility with older systems, Apple shipped these fonts, a TrueType Extension and a TrueType-aware version of Font/DA Mover for System Software 6. For compatibility with the Laserwriter II, Apple developed fonts like ITC Bookman and ITC Chancery in TrueType format.

All of these fonts could now scale to all sizes on screen and printer, making the Macintosh System 7 the first OS to work without any bitmap fonts. The early TrueType systems — being still part of Apple's QuickDraw graphics subsystem — did not render Type 1 fonts on-screen as they do today. At the time, many users had already invested considerable money in Adobe's still proprietary Type 1 fonts. As part of Apple's tactic of opening the font format versus Adobe's desire to keep it closed to all but Adobe licensees, Apple licensed TrueType to Microsoft. When TrueType and the license to Microsoft was announced, John Warnock of Adobe gave an impassioned speech in which he claimed Apple and Microsoft were selling snake oil, and then announced that the Type 1 format was open for anyone to use.

Meanwhile, in exchange for TrueType, Apple got a license for TrueImage, a PostScript-compatible page-description language owned by Microsoft that Apple could use in their laser printers. This was never actually included in any Apple products when a later deal was struck between Apple and Adobe, where Adobe promised to put a TrueType interpreter in their PostScript printer boards. Apple renewed its agreements with Adobe for the use of PostScript in its printers, resulting in lower royalty payments to Adobe, who was beginning to license printer controllers capable of competing directly with Apple's LaserWriter printers.

Part of Adobe's response to learning that TrueType was being developed was to create the Adobe Type Manager software to scale Type 1 fonts for anti-aliased output on-screen. Although ATM initially cost money, rather than coming free with the operating system, it became a de facto standard for anyone involved in desktop publishing. Anti-aliased rendering, combined with Adobe applications' ability to zoom in to read small type, and further combined with the now open PostScript Type 1 font format, provided the impetus for an explosion in font design and in desktop publishing of newspapers and magazines.

Apple extended TrueType with the launch of TrueType GX in 1994, with additional tables in the sfnt which formed part of QuickDraw GX. This offered powerful extensions in two main areas. First was font axes (morphing), for example allowing fonts to be smoothly adjusted from light to bold or from narrow to extended — competition for Adobe's "multiple master" technology. Second was Line Layout Manager, where particular sequences of characters can be coded to flip to different designs in certain circumstances, useful for example to offer ligatures for "fi", "ffi", "ct", etc. while maintaining the backing store of characters necessary for spell-checkers and text searching. However, the lack of user-friendly tools for making TrueType GX fonts meant there were no more than a handful of GX fonts.

Much of the technology in TrueType GX, including morphing and substitution, lives on as AAT (Apple Advanced Typography) in macOS. Few font-developers outside Apple attempt to make AAT fonts; instead, OpenType has become the dominant sfnt format despite its lack of support for axes or multiple masters.

Adoption by Microsoft

To ensure its wide adoption, Apple licensed TrueType to Microsoft for free. By 1991 Microsoft added TrueType into the Windows 3.1 operating system. In partnership with their contractors, Monotype Corporation, Microsoft spent much effort creating a set of high quality TrueType fonts that were compatible with the core fonts being bundled with PostScript equipment at the time. This included the fonts that are standard with Windows to this day: Times New Roman (compatible with Times Roman), Arial (compatible with Helvetica) and Courier New (compatible with Courier). One should understand "compatible" to mean two things: first, that the fonts are similar in appearance, and second — and very importantly — the fonts have the same character widths, and so can be used to typeset the same documents without reflowing the text.

Microsoft and Monotype technicians used TrueType's hinting technology to ensure that these fonts did not suffer from the problem of illegibility at low resolutions, which had previously forced the use of bitmapped fonts for screen display. Subsequent advances in technology have introduced first anti-aliasing, which smooths the edges of fonts at the expense of a slight blurring, and more recently subpixel rendering (the Microsoft implementation goes by the name ClearType), which exploits the pixel structure of LCD based displays to increase the apparent resolution of text. Microsoft has heavily marketed ClearType, and sub-pixel rendering techniques for text are now widely used on all platforms.

Microsoft also developed a "smart font" technology, named TrueType Open in 1994, later renamed to OpenType in 1996 when it merged support of the Adobe Type 1 glyph outlines.

Macintosh and Microsoft Windows

TrueType has long been the most common format for fonts on classic Mac OS, Mac OS X, and Microsoft Windows, although Mac OS X and Microsoft Windows also include native support for Adobe's Type 1 format and the OpenType extension to TrueType (since Mac OS X 10.0 and Windows 2000). While some fonts provided with the new operating systems are now in the OpenType format, most free or inexpensive third-party fonts use plain TrueType.

Increasing resolutions and new approaches to screen rendering have reduced the requirement of extensive TrueType hinting. Apple's rendering approach on macOS ignores almost all the hints in a TrueType font, while Microsoft's ClearType ignores many hints, and according to Microsoft, works best with "lightly hinted" fonts.

Linux and other platforms

The FreeType project of David Turner has created an independent implementation of the TrueType standard (as well as other font standards in FreeType 2). FreeType is included in many Linux distributions.

There were potential patent infringements in FreeType 1 because parts of the TrueType hinting virtual machine were patented by Apple, a fact not mentioned in the TrueType standards. (Patent holders who contribute to standards published by a major standards body such as ISO are required to disclose the scope of their patents, but TrueType was not such a standard.) FreeType 2 includes an automatic hinter that analyzes glyph shapes and attempts to generate hints automatically, thus avoiding the patented technology. The automatic hinter generally improves the appearance of free or cheap fonts, for which hinting is often either nonexistent or automatically generated, but it can degrade the appearance of professional hand-hinted fonts, and does not work well (or at all) for non-Western text that requires a different approach to hinting. As a result, some users chose to enable the patented hinting technology. As of May 2010, all patents related to bytecode hinting have expired worldwide, so FreeType 2.4 now enables these features by default.