What is the difference between the Unicode character properties “Ideographic” and “Unified_Ideograph”?
The Unified_Ideograph property (short name: UIdeo) is used to specify the exact set of CJK Unified Ideographs in the standard. In other words, it is applied only to unified ideographs, and not to compatibility ideographs or other characters that behave like ideographs, and it is only used specifically for the CJK ideographs— characters in the Han script. The Ideographic property (short name: Ideo), on the other hand, is extended to all CJK ideographs—not just the unified ones. It also applies to certain characters, such as U+3000 IDEOGRAPHIC SPACE, which behave like CJK ideographs, even though they are not formally considered part of the CJK Unified Ideographs. Furthermore, the Ideographic property is not constrained to apply only to Han script characters.
