In JavaScript, what does the '===' operator check for?

The '===' operator in JavaScript is known as the strict equality operator. It checks for both value and type equality, meaning that it will only return true if both the values being compared are identical in both type and value. For example, when comparing a number and a string, even if they represent the same numeric value (e.g., 5 and "5"), the strict equality operator will return false because their types differ.

This ensures that no type coercion occurs during the comparison. Type coercion refers to JavaScript's ability to automatically convert one type to another when performing operations, which can lead to unexpected results with the loose equality operator (==). By using '===', you can avoid these pitfalls and ensure that your comparisons are clear and precise.

In conclusion, the '===' operator is essential for situations where you need to confirm that two variables represent the same exact value and type, making it a reliable choice for strict comparisons in your JavaScript code.