Reverse Polish

Reverse Polish Notation is a mathematical notation, in which the operator follows the operands. The result is the removal of the need for parenthesis, because each operation only applies to a fixed number of values. You start from left to right and move to the first operator, this applies to the 2 previous terms.

You then move to the next operator to the right.

For example: "3 4 +" is equal to 7, 3 + 4 using Infix notation.

"3 4 + 2 *" is equal to 14, (3+4)*2. Because the operator applies to only two values (in this case) before it, there is no need for parenthesis.