and zero width characters with buttons for copying to clipboard, short mnemonics and usage comments.
→ No-breaking, mnemonic
HTML, mobdev
Mnemonic
Mobdev
iOS & Android
Zero Width
Expands when fully justified like typical space. Used with languages without visible space between words. Not supported in Internet Explorer v.6 and earlier.
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Doesn't produce any space and prohibits a line break at its position. Determines word borders for computer search, parsing, sorting, etc. Not a space character.
Classic
Minimal width.
Mostly 1/5 of type size, rarely 1/6.
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Frequently similar to Thin Space. Not rendered in Safari, so there's a hack.