What is the difference between var, let and const in JavaScript?

Var, let and const are used to declare a variables in JavaScript. A variable is a container that holds a value.
DIFFERENCE BETWEEN VAR, LET AND CONST.

1. Var has a function scope: this mean the variable is accessible throughout the entire functions regardless of the block it's in. Let has a blocked scope: this means that the variable is only accessible within the block it's declared it. This is the same with Const.
2. Var allows re-assignment of the same variable multiple times within the same scope Let does not allow re-assignment of the same variable within the same scope Const does not allow re-assignment of the same variable within the same scope

Why is it recommended to const for JavaScript

1. In const a variable declared cannot be re-assigned.This helps prevent unintended changes to the variable assigned.
2. Prevents accidental re-assignment.

Comments

[Stephen Gbolagade]

Hello @akinsanya_toluwanimi_e409

Allow me to correct a few things here:

Let allows reassignment but does not allow redeclaration in the same scope

For Instance:

let a = 7
a = 10 // you have reassign 10 to a which is allowed

but you cannot say:

let a = 7
let a = 10 // this is redeclaration and it's not allowed.

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