22.214.171.124.5. Case mappings
In addition to uppercase and lowercase, because of the inclusion of certain
composite characters for compatibility, such as "01F1;LATIN CAPITAL LETTER
DZ", there is a third case, called titlecase, which is used where the first
character of a word is to be capitalized (e.g. UPPERCASE, Titlecase,
lowercase). An example of such a character is "01F2;LATIN CAPITAL LETTER D
WITH SMALL LETTER Z".
The uppercase, titlecase and lowercase fields are only included for characters
that have a single corresponding character of that type. Composite characters
(such as "339D;SQUARE CM") that do not have a single corresponding character
of that type can be cased by decomposition.
The case mapping is an informative, default mapping. Certain languages, such
as Turkish, German, French, or Greek may have small deviations from the
default mappings listed in the Unicode Character Database.