Apple ColorLaserWriter 12/600PS - Manual (Page 303)

QuickDraw GX imaging technology
A QuickDraw GX font is a TrueType or PostScript font with an additional set
of sophisticated features. These features include extremely accurate
typographic elements such as ligatures and kerning, plus the ability to skew,
rotate, and add perspective to text in extremely flexible ways.
QuickDraw GX is more than a font format; it’s a sophisticated printing and
display technology that supports complex graphics and advanced typography.
How TrueType fonts work with other kinds of fonts
Although TrueType fonts offer distinct advantages, your Color LaserWriter
12/600 PS printer can also use other kinds of fonts.
TrueType and bitmapped fonts
Macintosh computers running System 7 come with both bitmapped (screen)
fonts and TrueType fonts installed. This maintains consistency with
documents created on Macintosh systems that don’t have TrueType fonts.
If both a TrueType and bitmapped version of the same font are available, the
Macintosh uses the bitmapped font (providing that the stipulated point size is
present). If you want the Macintosh to use the TrueType font, you need to
remove the bitmapped font from your system.
281 Using Fonts With the Printer