JavaScript Comparison Operators

JavaScript comparison operators are used to compare values and return a Boolean (true or false). They are essential for decision-making in JavaScript, helping to control the flow of programs by evaluating conditions.

Working of Comparison Operators

1. == (Equal To)

The == operator checks if two values are equal. It does not check the type, meaning it will convert data types to match if necessary.

Example:

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console.log(5 == "5");  // Output: true

Explanation: Although one is a number and the other is a string, == considers them equal because their values are the same after type conversion.

2. === (Strict Equal To)

The === operator checks if two values are equal and of the same type. It ensures no type conversion happens.

Example:

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console.log(5 === "5");  // Output: false

Explanation: Here, 5 (number) is not strictly equal to "5" (string), so the result is false.

3. != (Not Equal)

The != operator checks if two values are not equal. Like ==, it does not consider the type.

Example:

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console.log(5 != "5");  // Output: false

Explanation: The values are the same after type conversion, so != returns false.

4. !== (Strict Not Equal)

The !== operator checks if two values are not equal or if their types are different.

Example:

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console.log(5 !== "5");  // Output: true

Explanation: Since 5 (number) and "5" (string) are of different types, !== returns true.

5. > (Greater Than)

The > operator checks if the value on the left is greater than the value on the right.

Example:

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console.log(10 > 5);  // Output: true

Explanation: 10 is greater than 5, so the result is true.

6. < (Less Than)

The < operator checks if the value on the left is less than the value on the right.

Example:

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console.log(3 < 7);  // Output: true

Explanation: 3 is less than 7, so the result is true.

7. >= (Greater Than or Equal To)

The >= operator checks if the value on the left is greater than or equal to the value on the right.

Example:

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console.log(8 >= 8);  // Output: true

Explanation: 8 is equal to 8, so >= returns true.

8. <= (Less Than or Equal To)

The <= operator checks if the value on the left is less than or equal to the value on the right.

Example:

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console.log(4 <= 9);  // Output: true

Explanation: 4 is less than 9, so the result is true.

9. ? (Ternary Operator)

The ? operator, also known as the ternary operator, is a shorthand for the if...else statement. It allows you to execute one of two expressions based on a condition.

Syntax:

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condition ? expressionIfTrue : expressionIfFalse;

Note: We will discuss if...else statement in upcoming lessons.

Example:

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let age = 20;
let status = (age >= 18) ? "Adult" : "Minor";
console.log(status);  // Output: Adult

Explanation: Since age is 20, which is greater than or equal to 18, the ternary operator returns "Adult".