Word joiner explained

Word joiner should not be confused with Zero-width joiner.

The word joiner (WJ) is a Unicode format character which is used to indicate that line breaking should not occur at its position.^[1] It does not affect the formation of ligatures or cursive joining and is ignored for the purpose of text segmentation.^[1] It is encoded since Unicode version 3.2 (released in 2002) as .

The word joiner replaces the zero-width no-break space (ZWNBSP, U+FEFF), as a usage of the no-break space of zero width. The ZWNBSP is originally and currently used as the byte order mark (BOM) at the start of a file. However, if encountered elsewhere, it should, according to Unicode, be treated as a word joiner, a no-break space of zero width.

The deliberate use of U+FEFF for this purpose is deprecated as of Unicode 3.2, with the word joiner strongly preferred.^{[1] [2]}

See also

• Byte order mark, which uses (ZWNBSP) character
• Zero-width space
• Zero-width joiner, which in scripts such as Arabic or Indic causes two characters to be shown in a connected form, even if they would otherwise not.

References

Notes and References

1. Book: The Unicode Standard, Version 12.0.0. The Unicode Consortium. Layout Controls. 871. https://www.unicode.org/versions/Unicode12.0.0/ch23.pdf#G12985.
2. https://www.unicode.org/faq/utf_bom.html#bom6 FAQ - UTF-8, UTF-16, UTF-32 & BOM, ”What should I do with U+FEFF in the middle of a file?“