Postscript Type 1 fonts can be installed on the Macintosh only by using accompanying bitmapped fonts.
Postscript Type 3 fonts are installed on the Macintosh in the same way that Type 1 fonts are.
Truetype fonts: no bitmapped font is necessary with this type, though commonly used sizes are often supplied.
Bitmap fonts: on the Macintosh, bitmap fonts also contain the kerning information for a font and must be installed with both type 1 and type 3 fonts. Their presence also speeds the display of commonly used font sizes.