CFF - PostScript font program (Compact Font Format) table (OpenType 1.4)
This table contains a compact representation of a PostScript Type 1, or CIDFont and is structured according to Adobe Technical Note #5176: "The Compact Font Format Specification," and Adobe Technical Note #5177: "Type 2 Charstring Format."
Existing TrueType fonts use a glyph index to specify and access glyphs within a font, e.g. to index the loca table and thereby access glyph data in the glyf table. This concept is retained in OpenType™ PostScript fonts except that glyph data is accessed through the CharStrings INDEX of the CFF table.
OpenType specification