Prefix notation is a mathematical system of writing where operators are placed before their operands. Also known as Polish notation, it was invented by mathematician Jan Łukasiewicz in the 1920s. While "prefix notation" is the most commonly used term, there are other synonyms that refer to the same thing. These include "Polish notation," "prefix order," "prefix form," and "prefix notation form." Regardless of the term used, prefix notation is widely used in computer programming and appears in a variety of programming languages. Its main advantage is that it eliminates the need for parentheses, making it easier to write and read complex mathematical expressions.