Access All AlternatesThis feature makes all variations of a selected character accessible. This serves several purposes: An application may not support the feature by which the desired glyph would normally be accessed; the user may need a glyph outside the context supported by the normal substitution, or the user may not know what feature produces the desired glyph. Since many-to-one substitutions are not covered, ligatures would not appear in this table unless they were variant forms of another ligature.
Case-Sensitive FormsShifts various punctuation marks up to a position that works better with all-capital sequences or sets of lining figures; also changes oldstyle figures to lining figures. By default, glyphs in a text face are designed to work with lowercase characters. Some characters should be shifted vertically to fit the higher visual center of all-capital or lining text. Also, lining figures are the same height (or close to it) as capitals, and fit much better with all-capital text.
Discretionary LigaturesReplaces a sequence of glyphs with a single glyph which is preferred for typographic purposes. This feature covers those ligatures which may be used for special effect, at the user's preference.
FractionsReplaces figures separated by a slash with 'common' (diagonal) fractions.
KerningAdjusts amount of space between glyphs, generally to provide optically consistent spacing between glyphs. Although a well-designed typeface has consistent inter-glyph spacing overall, some glyph combinations require adjustment for improved legibility. Besides standard adjustment in the horizontal direction, this feature can supply size-dependent kerning data via device tables, "cross-stream" kerning in the Y text direction, and adjustment of glyph placement independent of the advance adjustment. Note that this feature may apply to runs of more than two glyphs, and would not be used in monospaced fonts. Also note that this feature does not apply to text set vertically.
Standard LigaturesReplaces a sequence of glyphs with a single glyph which is preferred for typographic purposes. This feature covers the ligatures which the designer/manufacturer judges should be used in normal conditions.
OrnamentsThis is a dual-function feature, which uses two input methods to give the user access to ornament glyphs (e.g. fleurons, dingbats and border elements) in the font. One method replaces the bullet character with a selection from the full set of available ornaments; the other replaces specific "lower ASCII" characters with ornaments assigned to them. The first approach supports the general or browsing user; the second supports the power user.
