# reverse Polish notation

**reverse Polish notation ( RPN; postfix notation; suffix notation)** A form of notation, invented by the Polish mathematician Jan Lukasiewicz, in which each operator follows its operands. Thus, for example,

*a*+

*b*is written

*ab*+

*a*+

*b*∗

*c*is written

*abc*∗+

If each operator has a specific number of operands (e.g. if all operators take exactly two operands), then no brackets are required since the order of evaluation is always uniquely defined; the notation can then be described as

*parenthesis-free*.

The importance of RPN is that an expression in this form can be readily evaluated on a stack. Thus translation to RPN, followed by stack evaluation, is a simple but effective strategy for dealing with arithmetic expressions in a programming language. See also Polish notation.

#### More From encyclopedia.com

#### You Might Also Like

#### NEARBY TERMS

**reverse Polish notation**