Unicode and Emoji Glossary
21 terms explained in plain language, with examples. These are the words that turn up when an emoji does not behave the way you expected — in a bug report, a spec, or a character-count error.
Core concepts
Terms with enough behind them to be worth a page of their own.
Code point
A code point is a single number assigned to one character in the Unicode standard, written as U+ followed by hexadecimal digits.
Grapheme cluster
A grapheme cluster is the group of code points a reader perceives as one character — which is why an emoji family counts as one character on screen but seven in code.
Zero width joiner (ZWJ)
The zero width joiner (U+200D) is an invisible character that tells a font to merge the emoji on either side of it into one picture.
Variation selector
Variation selectors VS15 (U+FE0E) and VS16 (U+FE0F) request the text or emoji appearance of a character that has both.
Regional indicator
Regional indicator symbols are 26 letter-shaped code points that combine in pairs to form flag emoji from ISO country codes.
Skin tone modifier
Five modifier characters (U+1F3FB–U+1F3FF) follow a supported emoji to select one of the Fitzpatrick-based skin tones.
RGI emoji
RGI stands for "recommended for general interchange" — the subset of possible emoji sequences that Unicode expects every vendor to support.
CLDR
The Common Locale Data Repository supplies the translated short names and search keywords used for emoji in each language.
Quick definitions
Shorter terms, defined here in full — a separate page for each would add nothing.
- Unicode
- Unicode is the standard that assigns a unique number to every character used in the world's writing systems, including emoji.
- Glyph
- A glyph is the actual drawn shape a font uses to display a character — one character can have many glyphs across different fonts.
- Emoji
- Emoji are pictographic characters defined by Unicode and drawn by the fonts installed on your device.
- Emoticon
- An emoticon is a face built from ordinary punctuation, such as :-), rather than a dedicated character.
- Kaomoji
- Kaomoji are Japanese-style text faces read upright, assembled from letters and symbols such as (╯°□°）╯.
- Emoji presentation
- Emoji presentation is the colourful pictorial rendering of a character, as opposed to its monochrome text form.
- Text presentation
- Text presentation is the monochrome, typeface-styled rendering of a character that also has an emoji form.
- Combining character
- A combining character attaches to the character before it, adding an accent or other mark without occupying its own space.
- Unicode block
- A block is a contiguous, named range of code points, such as Arrows (U+2190–U+21FF), used to organise the standard.
- UTF-8
- UTF-8 stores each code point as one to four bytes and is the dominant encoding on the web.
- UTF-16
- UTF-16 stores each code point as one or two 16-bit units; JavaScript string lengths are measured in these units.
- HTML entity
- An HTML entity writes a character using its code point, such as 😂, so it survives files with a limited encoding.
- Shortcode
- A shortcode such as :joy: is a platform-specific text alias for an emoji; it is not part of the Unicode standard.
Where these definitions come from
Each definition describes what the Unicode standard specifies, written by the SymbolTap editorial side rather than quoted. Terms defined normatively by Unicode link to the relevant report so you can read the exact wording. Where a term is a convention rather than part of the standard — shortcodes, for instance — the entry says so.
Last reviewed 31 July 2026.