Here are a few title options, all in question format, which capture the key points of your article: * **Null vs. Undefined: When to Use `==` and When to Use `===` in JavaScript?** * **JavaScript\'s N

Distinguishing Null and Undefined Values and Understanding the Differences Between == and ===

Null vs. Undefined: Understanding the Absence of Values

In JavaScript, null and undefined play crucial roles in indicating the absence of values.

• Undefined represents the default value of uninitialized variables, function arguments left unassigned, and property values not found in objects. It also serves as an explicit assignment to indicate a missing value.
• Null is a more specific type indicating a blank object reference. It is commonly used in APIs like DOM to indicate a non-existing element or object.

Checking for Null and Undefined

To determine if a variable is null, use any of the following options:

• if (a === null)
• if (a == null) (Note: This also matches undefined, so use with caution)

To check for undefined, consider the following:

• if (typeof a === "undefined")
• if (a === undefined)
• if (a == undefined) (Note: This can also match null, so exercise caution)

Type Coercion with == vs. Strictly Equal with ===

The == operator performs type coercion to compare values, while === performs strict equality checks without type coercion.

For example:

"1" == 1 // True (type coercion converts "1" to 1)
"1" === 1 // False (strict equality checks for same type and value)

The === operator is generally recommended for strict value and type comparisons.

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