What is the primary difference between '==' and '===' in JavaScript?

In JavaScript, the distinction between '==' and '===' is crucial for understanding how comparisons operate. The operator '==' is known as the equality operator, and it checks for value equality while allowing for type coercion. This means that if the values being compared are of different types, JavaScript will attempt to convert them into a common type before making the comparison. For example, if you compare a string '5' with a number 5, JavaScript will convert the string to a number and they will be considered equal.

On the other hand, '===' is the strict equality operator, which checks for both value and type equality without any coercion. This means that if the types of the values being compared are not the same, the comparison will return false, even if their values are equivalent. For instance, '5' (string) and 5 (number) are not strictly equal, so '5' === 5 would result in false.

Understanding this difference helps in writing more predictable and error-free code, especially when comparing variables of different types. This makes option C the correct answer, as it accurately describes the behavior of both operators in JavaScript.