A maplet or maplet arrow (symbol: ↦, commonly pronounced "maps to") is a symbol consisting of a vertical line with a rightward-facing arrow. It is used in mathematics and in computer science to denote functions (the expression x ↦ y is also called a maplet). One example of use of the maplet is in Z notation, a formal specification language used in software development.
In the Unicode character set, the maplet is at the point U+21A6.
References
Maplet Wikipedia(Text) CC BY-SA