Name | Description |
GSUB | Contains information about glyph substitutions to handle single glyph substitution, one-to-many substitution (ligature decomposition), aesthetic alternatives, multiple glyph substitution (ligatures), and contextual glyph substitution. |
GPOS | Contains information about X and Y positioning of glyphs to handle single glyph adjustment, adjustment of paired glyphs, cursive attachment, mark attachment, and contextual glyph positioning. |
BASE | Contains information about baseline offsets on a script-by-script basis. |
JSTF | Contains justification information, including whitespace and Kashida adjustments. |
GDEF | Contains information about all individual glyphs in the font: type (simple glyph, ligature, or combining mark), attachment points (if any), and ligature caret (if a ligature glyph). |