In Display PostScript, every face of every font is defined by a PostScript program (see the PostScript® Language Reference Manual for more details on how to create a PostScript font). In order for the NEXTSTEP system to use a font, the font creator must provide the PostScript language file defining the outlines of the characters of the font, and an Adobe Font Metrics (AFM) file describing separately the widths of those characters.
In NEXTSTEP a font is stored in the filesystem as a directory whose name is that of the font, followed by a .font extension; for example, Helvetica-Oblique.font. The .font directory must contain at least the outline and afm files for the font, and optionally the bitmap file for the font. So, Helvetica-Oblique.font would contain the outline file Helvetica-Oblique, the AFM file Helvetica-Oblique.afm, and possibly Helvetica-Oblique.bepf (see below). Some fonts also have AFM files for specific point sizes of screen bitmap fonts; for example, Screen-Helvetica-Oblique.10.afm for 10-point Helvetica Oblique.
In order for the window server to see a new font, it must be placed in one of the three standard Fonts directories: /NextLibrary/Fonts, /LocalLibrary/Fonts, or ~/Library/Fonts.
prebuild outputs a file in the current directory whose name is the name of the font followed by the suffix indicating the byte sex of the file (.bepf for big-endian files, and .lepf for little-endian files). This file should be placed in the same font's .font directory.
/NextLibrary/Fonts/ location of NeXT-provided fonts /LocalLibrary/Fonts/ location of local fonts ~/Library/Fonts/ location of user fonts
screenafm(1)
fonttype and fontuniqueid are actually ignored.