postfix

computer science

Also known as: reverse Polish notation

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Last updated

July 19, 2026

Quick Summary

Postfix notation, also known as reverse Polish notation (RPN), is a system for representing mathematical and logical operations. In this system, operands come before the operator, eliminating the need for parentheses. For example, the expression (3 + 5) - (2 + 1) is written as 3 5 + 2 1 + - in postfix notation. This method places operators after their operands, distinguishing it from infix (standard) and prefix notation. It was first used in 1957.123

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PostScript
PostScript uses postfix, also called reverse Polish notation, in which an operation name follows its arguments. Thus, “300 600 20 270 arc stroke” means: draw (“stroke”) a 270-degree arc with radius 20 at location (300, 600). Although PostScript can be read and written by a programmer, it…
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PostScript uses postfix, also called reverse Polish notation, in which an operation name follows its arguments. Thus, “300 600 20 270 arc stroke” means: draw (“stroke”) a 270-degree arc with radius 20 at location (300, 600). Although PostScript can be read and written by a programmer, it…
Read More