What is `NaN` in JavaScript?

Description : `NaN` stands for 'Not-a-Number' and is a value that results from an invalid or undefined mathematical operation.

Answer :

`NaN` is a special value in JavaScript that represents a value that is not a legal number. It is returned when a mathematical operation fails or when a function that expects a number receives a non-numeric value. Interestingly, `NaN` is the only value in JavaScript that is not equal to itself, making it easy to check if a value is `NaN` using `Number.isNaN()`. 

console.log(0 / 0); // NaN
console.log(parseInt('abc')); // NaN

console.log(NaN === NaN); // false
console.log(Number.isNaN(NaN)); // true

`NaN` is a special value in JavaScript that represents a value that is not a legal number. It is returned when a mathematical operation fails or when a function that expects a number receives a non-numeric value. Interestingly, `NaN` is the only value in JavaScript that is not equal to itself, making it easy to check if a value is `NaN` using `Number.isNaN()`. 

console.log(0 / 0); // NaN
console.log(parseInt('abc')); // NaN

console.log(NaN === NaN); // false
console.log(Number.isNaN(NaN)); // true

Category : Javascript

Created Date : 9/6/2024

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What is the `String.prototype.anchor` method in JavaScript?

What is the `String.prototype.anchor` method in JavaScript?

More details

2024-09-06 last updatedFreeJavascript

`String.prototype.anchor` creates an HTML `<a>` element wrapping the string with a specified name attribute. This method is deprecated and should not be used in modern applications. 

const str = 'Click here';
const anchoredStr = str.anchor('top');
console.log(anchoredStr); // '<a name="top">Click here</a>'

`String.prototype.anchor` creates an HTML `<a>` element wrapping the string with a specified name attribute. This method is deprecated and should not be used in modern applications. 

const str = 'Click here';
const anchoredStr = str.anchor('top');
console.log(anchoredStr); // '<a name="top">Click here</a>'

`String.prototype.anchor` creates an HTML `<a>` element wrapping the string with a specified name attribute. This method is deprecated and should not be used in modern applications. 

const str = 'Click here';
const anchoredStr = str.anchor('top');
console.log(anchoredStr); // '<a name="top">Click here</a>'

`String.prototype.anchor` creates an HTML `<a>` element wrapping the string with a specified name attribute. This method is deprecated and should not be used in modern applications. 

const str = 'Click here';
const anchoredStr = str.anchor('top');
console.log(anchoredStr); // '<a name="top">Click here</a>'

What is the `String.prototype.small` method in JavaScript?

What is the `String.prototype.small` method in JavaScript?

More details

2024-09-06 last updatedFreeJavascript

`String.prototype.small` returns a string wrapped in HTML `<small>` tags. This method is deprecated and should not be used in modern applications. 

const str = 'hello';
const smallStr = str.small();
console.log(smallStr); // '<small>hello</small>'

`String.prototype.small` returns a string wrapped in HTML `<small>` tags. This method is deprecated and should not be used in modern applications. 

const str = 'hello';
const smallStr = str.small();
console.log(smallStr); // '<small>hello</small>'

`String.prototype.small` returns a string wrapped in HTML `<small>` tags. This method is deprecated and should not be used in modern applications. 

const str = 'hello';
const smallStr = str.small();
console.log(smallStr); // '<small>hello</small>'

`String.prototype.small` returns a string wrapped in HTML `<small>` tags. This method is deprecated and should not be used in modern applications. 

const str = 'hello';
const smallStr = str.small();
console.log(smallStr); // '<small>hello</small>'