Zero-width joiner

Non-printing character used in computerized typesetting

The zero-width joiner is a non-printing character used in the computerized typesetting of writing systems in which the shape or positioning of a grapheme depends on its relation to other graphemes, such as the Arabic script or any Indic script. Sometimes the Roman script is to be counted as complex, e.g. when using a Fraktur typeface. When placed between two characters that would otherwise not be connected, a ZWJ causes them to be printed in their connected forms.

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