The double question mark operator, denoted as ??, is a logical operator in JavaScript that evaluates to its right-hand side operand if the left-hand side operand is null or undefined. Otherwise, it evaluates to its left-hand side operand. This operator is commonly used for assigning a default value to a variable when the variable may be null or undefined.
One of the key benefits of using the double question mark operator is that it provides a concise and readable way to handle null and undefined values. It eliminates the need for lengthy if-else statements or ternary operators, making the code more succinct and easier to understand.
