JavaScript Variables Interview Questions & Answers

Q1. What is a Variable in JavaScript?

A variable is a container used to store data values. It allows developers to store, update, and reuse data in a program.

Example

let name = "John";
console.log(name);

Output

John

Here, name is a variable that stores the value "John".

Q2. How Do You Declare Variables in JavaScript?

JavaScript provides three keywords to declare variables:

Example

var age = 20;
let city = "London";
const country = "UK";

Each keyword has different behavior and usage rules.

Q3. What is Variable Scope?

Scope defines where a variable can be accessed in the program.

Types of Scope

1. Global Scope
Variable cna be accessed anywhere.

let name = "Alex";

2. Block Scope
Variable can only be accessed inside a block { }.

{
    let age = 25;
}

Q4. What is Variable Initialization?

Initialization means assigning a value to a variable when it is declared.

Example

let score = 100;

Here:

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