This character is a Otro símbolo and is commonly used, that is, in no specific script.
The glyph is not a composition. It has no designated width in East Asian texts. In bidirectional text it acts as Other Neutral. When changing direction it is not mirrored. The word that U+21D0 forms with similar adjacent characters prevents a line break inside it.
The CLDR project calls this character “flecha doble hacia la izquierda” for use in screen reading software. It assigns these additional labels, e.g. for search in emoji pickers: doble, flecha, izquierda.
El Wikipedia tiene la siguiente información acerca de este punto de código:
An arrow is a graphical symbol, such as ← or →, or a pictogram, used to point or indicate direction. In its simplest form, an arrow is a triangle, chevron, or concave kite, usually
affixed to a line segment or rectangle, and in more complex forms a representation of an actual arrow (e.g. ➵ U+27B5). The direction indicated by an arrow is the one along the length of the line or rectangle toward the single pointed end.
Representaciones
Sistema
Representación (click value to copy)
N.º
8656
UTF-8
E2 87 90
UTF-16
21 D0
UTF-32
00 00 21 D0
URL-Quoted
%E2%87%90
HTML hex reference
⇐
Mojibake mal de windows-1252
â‡
HTML named entity
⇐
HTML named entity
⇐
HTML named entity
⇐
Codificación: GB18030 (hexadecimales bytes)
81 36 CC 38
LATEX
\Leftarrow
Adobe Glyph List
arrowdblleft
Adobe Glyph List
arrowleftdbl
dígrafo
<=
RFC 5137
\u'21D0'
Bash and Zsh inside echo -e
\u21D0
C and C++
\u21D0
C#
\u21D0
CSS
\0021D0
Excel
=UNICHAR(8656)
Go
\u21D0
JavaScript
\u21D0
Modern JavaScript since ES6
\u{21d0}
JSON
\u21D0
Java
\u21D0
Lua
\u{21D0}
Matlab
char(8656)
Perl
"\x{21D0}"
PHP
\u{21d0}
PostgreSQL
U&'\21D0'
PowerShell
`u{21D0}
Python
\u21D0
Ruby
\u{21d0}
Rust
\u{21d0}
Haga clic en el botón de estrella junto a cada etiqueta para establecer esta representación como favorita o eliminarla de las favoritas. Las favoritas se mostrarán inicialmente. (Los favoritos se almacenan localmente en su equipo y no se envían nunca por Internet)