What's the Difference Between JavaScript's =, ==, and === Operators?

Understanding the Differences Between the =, ==, and === Operators in JavaScript

As you noticed in your code, the use of different operators (= and ==) can be confusing when working with equality checks. To clarify, let's dive deeper into the purpose and functionality of each operator:

The = Operator: Assignment

In JavaScript, the = operator is used for variable assignment. It sets a variable on the left-hand side to the value specified on the right-hand side. For example, in the code snippet you provided:

$("#block").css.display = "block";

The = operator sets the display property of the #block element to the value "block."

The == Operator: Loose Equality Comparison

The == operator performs a loose equality comparison. This means it compares the values of two operands after attempting to coerce them into the same type. For instance:

"1" == 1; // true

Here, the string "1" is automatically coerced to the number 1, making them equivalent. However, it's important to note that the types are not identical, so this comparison is considered "loose."

The === Operator: Strict Equality Comparison

The === operator, also known as the "identity operator," performs a strict equality comparison. Unlike ==, it checks not only the value but also the type of the operands. This ensures that the values being compared are of the same type. For example:

"1" === 1; // false

In this case, the comparison fails because the type of "1" is a string, while the type of 1 is a number.

As mentioned in the provided solution, resources such as Codecademy and MDN offer comprehensive introductions to JavaScript concepts. For specific information on the "identity operator" term, you can refer to sources such as "JavaScript: The Definitive Guide."

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