Standard Ligatures

Tag: liga

Function: Replaces 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. The glyph for ffl replaces the sequence of glyphs f f l.

Contextual Alternates

Tag: calt

Function: In specified situations, replaces default glyphs with alternate forms which provide better joining behavior. Used in script typefaces which are designed to have some or all of their glyphs join. In Caflisch Script, o is replaced by o.alt2 when followed by an ascending letterform.

Tag: dpng

Function:

Historical Ligatures

Tag: hlig

Function: Some ligatures were in common use in the past, but appear anachronistic today. Some fonts include the historical forms as alternates, so they can be used for a 'period' effect. This feature replaces the default (current) forms with the historical alternates. The user applies this feature using Palatino Linotype, and historic ligatures are formed for all long s forms, including: long s+t, long s+b, long s+h, long s+k, and several others.

Terminal Forms

Tag: fina

Function: Replaces glyphs at the ends of words with alternate forms designed for this use. This is common in Latin connecting scripts, and required in various non-Latins like Arabic. In the typeface Poetica, the default e in the word 'type' is replaced with the e.end form.

Isolated Forms

Tag: isol

Function: Replaces the nominal form of glyphs with their isolated forms. In Arabic, if the Alef is followed by Lam, the default glyph for Alef is replaced with its isolated form.

Medial Forms

Tag: medi

Function: Replaces glyphs in the middles of words (i.e. following a beginning and preceding an end) with alternate forms designed for this use. Note: This is different from the default form, which is designed for stand-alone use. This is common in Latin connecting scripts, and required in various non-Latins like Arabic. In the typeface Caflisch Script, the y and p in the word 'type' are replaced by the y.med and p.med forms.