Reverse Polish Notation

Reverse Polish Notation not to be confused with Reverse Reverse Polish notation. It is Notation used for algebra that is easier for programers to parse. The alternative is to compute PEMDAS and that gets into abstract syntax trees. Since Reverse Polish Notation has a association with Stacks and Stack based programing paradigms it's usually found there.

Confused? If you are that's the point. Reverse polish notation was meant to be understood by people but it's still not as easy as pemdas. So that's why we use S-expressions or just pemdas.

Person A: Hey did you hear about that Reverse Polish Notation Calculator?
Person B: You living in the 1980s or something we use pemdas.

Example of Reverse polish notation:

9 2 3 + *is equvalient to (2 + 3)* 9