The capital Greek letter (capital Pi) is used in math to represent the product operator. Typically, the product operator is used in an expression like this:
In plain language, this means take the product of the sequence of expressions represented by the expression starting from and iterating until .
The greek small letter π (pi) is a geometric constant approximately equal to 3.1416. The numeric value is equal to the length of any circle's circumference divided by its diameter.
The product operator is represented by the Π (capital pi) symbol and is used to represent the operation of multiplying a sequence of expressions together.