What is the difference between `null` and `undefined` in JavaScript?

Description : `null` represents the intentional absence of any object value, while `undefined` indicates a variable has been declared but not yet assigned a value.

Answer :

`null` is an assignment value that represents the intentional absence of any object value. It is often used to reset or clear a variable. `undefined` means that a variable has been declared but has not yet been assigned a value. JavaScript will automatically assign `undefined` to variables that are declared but not initialized. 

let x;
console.log(x); // undefined

let y = null;
console.log(y); // null

console.log(typeof null); // 'object'
console.log(typeof undefined); // 'undefined'

`null` is an assignment value that represents the intentional absence of any object value. It is often used to reset or clear a variable. `undefined` means that a variable has been declared but has not yet been assigned a value. JavaScript will automatically assign `undefined` to variables that are declared but not initialized. 

let x;
console.log(x); // undefined

let y = null;
console.log(y); // null

console.log(typeof null); // 'object'
console.log(typeof undefined); // 'undefined'

Category : Javascript

Created Date : 9/6/2024

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`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';
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const str = 'Click here';
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`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. 

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

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

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`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>'

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

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

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