Canonical Combining Class - Han Reading

Han Reading is the term for how the canonical combining class value of zero applies to most Han ideographs, meaning these characters do not interact with adjacent marks during text normalization or reordering. In practice, this zero value ensures that each Chinese character retains its own visual identity and does not merge with diacritics or vowel signs, which is why clusters of Han characters remain stable and predictable in digital typography. A nonzero combining class would imply participation in complex script shaping, but Han characters are standalone, so their inherent zero class reflects their isolation from such processes, a key feature for faithful rendering of Chinese texts across fonts and platforms.