u21D5

u21D5 refers to the Unicode code point U+21D5, which is part of the Arrows block in the Unicode standard. The character is commonly described as a vertical bidirectional symbol, typically rendered as an up-and-down double-headed arrow. In many fonts the glyph appears as the symbol "⇕", though appearance can vary with typeface.

Encoding and representation: U+21D5 is encoded in UTF-8 as the three-byte sequence E2 87 95. In HTML, it can be represented as ⇕ or ⇍. As with other Unicode characters, actual rendering depends on font support for the Arrows block.

Usage and interpretation: The symbol is used in mathematical notation and diagramming to signify bidirectional movement, two-way processes, or synchronization between opposing directions. It can denote that a relationship or operation may proceed in either direction, or that two states are interconnected.

Related symbols: Other nearby arrows in Unicode include U+2195 (Up Down Arrow), often used to indicate a general bidirectional concept, and U+21D4 (Left Right Double Arrow), used for equivalence or bidirectional mapping. The Arrows block contains a variety of single, double, and combined arrow shapes for technical and linguistic purposes.

See also: Unicode Arrows block, Unicode encoding forms (UTF-8), and glyph rendering in fonts that support the symbol U+21D5.