Implementations
One popular and recognizable form of hinting is found in the TrueType font format, released in 1991 by Apple Computer. Hinting in TrueType invokes tables of font data used to render fonts properly on screen. One aspect of TrueType hinting is grid-fitting, which modifies the height and width of font characters to line up to the set pixel grid of screen display. The open-source FreeType 2 font rendering engine uses an auto-hinter when such hinting data is not present or its use is restricted by a software patent. As of 2011, the FreeType website states that the relevant font hinting patents have now all expired, and TrueType is now enabled in FreeType by default.
Read more about this topic: Font Hinting