Stacked diacritics are used in Thai and other Asian languages, as well as rarely-seen languages such as those of the Yukon.
The right-to-left control character is for embedding e.g. Arabic or Hebrew script inside Latin text (or vice versa). It is actually a controversial feature of Unicode as some people feel it belongs in a higher-level protocol.
The right-to-left control character is for embedding e.g. Arabic or Hebrew script inside Latin text (or vice versa). It is actually a controversial feature of Unicode as some people feel it belongs in a higher-level protocol.
Check out the examples here http://scripts.sil.org/cms/scripts/page.php?site_id=nrsi&id=... for an idea of what rendering non-Western scripts can entail.