Untitled

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Document</title>
</head>
<body>

    <script>
        document.addEventListener("DOMContentLoaded", function(event){

            function Product(name, price){
                this.name = name;
                this.price = price;
            }

            Product.prototype.printProduct = function(){
                console.log(this.name + " : " + this.price);
            }

            ketchup = new Product("ketchup", "5.99");
            mustard = new Product("mustard", "4.99");

            ketchup.printProduct();
            mustard.printProduct();

        });
    </script>
</body>
</html>