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Difference Between var, let, and const in JavaScript

This article is created to differentiate between var, let, and const in JavaScript. These three are the keywords, used to declare a variable in JavaScript.

var Vs let Vs const in JS

var	let	const
declares function-scoped or globally-scoped variable	declares block-scoped local variable	declares block-scoped variable
can be updated and re-declared	can be updated but cannot be re-declared	neither can be updated nor be re-declared
can be declared without initializing any value	can be declared without initializing any value	can not be declared without initializing any value

Note - Accessing a variable declared using var keyword without initialization, returns undefined.

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