JavaScript Built In Operator -- (Decrement Postfix)

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This is an operator designated for decrementing a value in math within JavaScript. Most commonly used in postfix (the -- after the variable), there is a prefix method also which is slightly different. In the prefix operator, the decrement takes place before the number or variable is used. Within parenthesis, they are the same. In an equation without parenthesis surrounding it, prefix or postfix precedence takes place. Compare this to Decrement prefix.