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Question 84 of 521

Part 2: Promises, Callbacks, Async & Strict Mode (54 - 103)

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JavaScript Internals (521 Qs)•Part 2: Promises, Callbacks, Async & Strict Mode (54 - 103)

What is isNaN

The isNaN() function is used to determine whether a value is an illegal number (Not-a-Number) or not. i.e, This function returns true if the value equates to NaN. Otherwise it returns false.

javascript
isNaN("Hello"); //true
isNaN("100"); //false
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