JavaScript JS Variables var, let & const

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JavaScript Beginner 1 min read

var, let & const

Take Quiz (1)

var, let & const

	var	let	const
Scope	Function	Block	Block
Re-assign	Yes	Yes	No

Best Practice

Use const by default. Use let when you need to reassign. Avoid var.

Example

const PI = 3.14;    // won't change
let count = 0;      // will change
count++;
const user = {};
user.name = 'Alice'; // OK — mutating object

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