Here are a few title options, capturing the essence of your provided text: **Direct & Concise:** * What\'s the Difference Between `null` and `undefined` in JavaScript? * JavaScript: `null` vs.

JavaScript: Distinguishing Null vs. Undefined and Comparing with == vs. ===

Checking for Null and Undefined

Checking for Null:

• Strict comparison: if (a === null)
• Loose comparison: if (a == null) (Caution: Will also return true for undefined)

Checking for Undefined:

• Type comparison: if (typeof a === "undefined")
• Strict comparison: if (a === undefined)
• Loose comparison: if (a == undefined) (Caution: Will also return true for null)

Difference Between Null and Undefined

• Undefined: Default value of uninitialized variables, omitted function arguments, and missing object properties. Denotes an "absence".
• Null: Specifically represents an empty object reference.

Difference Between == and ===

• == (Loose Equality): Performs type coercion to equate values (e.g., "1" == 1 is true).
• === (Strict Equality): Compares both value and type. Returns false if types differ (e.g., "1" === 1 is false).

Note: Strict comparison (===) is recommended for type-safe comparisons and avoiding unexpected results from type coercion.

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