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Combining Characters
How accents, strikethroughs and glitch effects attach to letters.
Short answer
A combining character has no width of its own — it draws on top of the character before it. That is how accents attach to letters, and how strikethrough and Zalgo effects are built.
Zero-width marks
A combining character has no width of its own — it renders on top of the character before it. That is how é can be written either as one precomposed character or as e followed by a combining acute accent.
Why it matters here
Strikethrough and underline styles work by appending a combining long stroke or low line to every character. Nothing is deleted or formatted; each letter simply carries a mark.
Two ways to write the same letter
The letter é can be a single precomposed character or an e followed by a combining acute accent. They look identical and mean the same thing, but they are different byte sequences, so a naive string comparison reports them as unequal. Unicode normalisation exists precisely to resolve this, converting text to a consistent form before comparison.
Why this matters beyond decoration
The same mechanism that produces glitch text underlies accented letters in most of the world's languages. Search, sorting and password comparison all depend on normalising these forms consistently — which is why a password containing an accented character can occasionally fail to match one that looks identical.
Read next
Sources
- Unicode Standard, Combining Diacritical Marks (U+0300–U+036F)
The zero-width marks used for strikethrough, underline and stacked glitch effects.