The zero-width space (ZWSP) is a non-printing character used in computerized typesetting to indicate where the word boundaries are, without actually displaying a visible space in the rendered text. This enables text-processing systems for scripts that do not use explicit spacing to recognize where word boundaries are for the purpose of handling line breaks appropriately. Zero-width space is unicode character U+200B, and is located in the unicode General Punctuation block, and can be represented by HTML entities ​or​.
The zero-width space marks a potential line break without hyphenation. Its semantics and HTML implementation are similar to the soft hyphen, but soft hyphens display a hyphen character at the point where the line is broken.
The zero-width space can be used to mark word breaks in languages without visible space between words, such as Thai, Myanmar, Khmer, and Japanese.[1][2]
Unlike fixed-width spaces, in justified text that increases spacing between letters, characters adjacent to the zero-width space are spaced as if it was not present.[2]
To show the effect of the zero-width space in text, the following words have been separated with zero-width spaces:
LoremIpsumDolorSitAmetConsecteturAdipiscingElitSedDoEiusmodTemporIncididuntUtLaboreEtDoloreMagnaAliquaUtEnimAdMinimVeniamQuisNostrudExercitationUllamcoLaborisNisiUtAliquipExEaCommodoConsequatDuisAuteIrureDolorInReprehenderitInVoluptateVelitEsseCillumDoloreEuFugiatNullaPariaturExcepteurSintOccaecatCupidatatNonProidentSuntInCulpaQuiOfficiaDeseruntMollitAnimIdEstLaborum
And the following words have not been separated with these spaces:
LoremIpsumDolorSitAmetConsecteturAdipiscingElitSedDoEiusmodTemporIncididuntUtLaboreEtDoloreMagnaAliquaUtEnimAdMinimVeniamQuisNostrudExercitationUllamcoLaborisNisiUtAliquipExEaCommodoConsequatDuisAuteIrureDolorInReprehenderitInVoluptateVelitEsseCillumDoloreEuFugiatNullaPariaturExcepteurSintOccaecatCupidatatNonProidentSuntInCulpaQuiOfficiaDeseruntMollitAnimIdEstLaborum
The first text only breaks at word boundaries, while the second text will not be broken at all. Resizing the browser window will re-break the text accordingly.
InHTML pages, the HTML element <wbr> functions as a zero-width space. In Internet Explorer 6, the zero-width space was not supported in some fonts.[3]
ICANN rules prohibit domain names from containing non-displayed characters, including the zero-width space, and most browsers prohibit their use within domain names because they can be used to create a homograph attack, where a malicious URL is visually indistinguishable from a legitimate one.[4][5]
The zero-width space character is encoded in UnicodeasU+200B ZERO WIDTH SPACE,[6] and input in HTML as ​, ​or​. Contrary to what their names suggest, the character entities ​, ​, ​, and ​ also refer to the zero-width space.[7]
The TeX representation is \hskip0pt; the LaTeX representation is \hspace{0pt};[8] and the groff representation is \:.[9]
Les espaces sans chasse sont conçues pour les langues qui ne séparent pas les mots à l'aide d'espaces visibles, comme le thaï ou le japonais.