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 (today known as variations), 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 variations 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, and all of the font variation technology is the de facto standard today in OpenType Variations. Adoption by Microsoft To ensure its wide adoption, Apple licensed TrueType to Microsoft for free. Microsoft added TrueType into the Windows 3.1 operating environment. In partnership with their contractors, Monotype Imaging, Microsoft put a lot of effort into creating a set of high quality TrueType fonts that were compatible with the core fonts being bundled with