Unicode Block - CJK Compatibility Ideographs
CJK Compatibility Ideographs is a collection of Chinese, Japanese, and Korean characters that were originally encoded in earlier industry standards, such as IBM and Apple character sets, to ensure compatibility with legacy systems before the unified Han ideographs were fully harmonized. These characters appear in the standard as duplicates or slightly variant forms of characters already found in the main CJK Unified Ideographs blocks, often representing regional or historical typographic differences. Because of this duplication, the Unicode standard recommends that implementers treat them as canonical equivalents to their unified counterparts when performing text normalization, though the compatibility ideographs retain their own distinct code points for round‑trip data conversion with older software.