Array is one of the most important thing in JavaScript. Without array you cannot imagine JavaScript. Array is combination of elements which are same type. There are total nine data types in JavaScript . You have to put same data type as a array elements.

Let’s make an array in number data type.

const evenNumber = [2, 4, 6, 8, 10];

now check this is array or not by the JavaScript method isArray.

Yep! This is an array. So now I will show you 10 methods which is so useful.


React is a JavaScript library. We can make single page application with react so easily. With react we create a virtual DOM. As a bigger you should some fundamental concept which makes you more comfortable to be a react developer.

1. What is react

React is a JavaScript library. This library develop by Facebook. With react we can make single page application. React is very popular because of it’s easiest ways. In react application we write html code with JavaScript. React application created base with components. You can think components just like function. We can reuse components as much as we want. …

1.Var Declaration and Hoisting:

what is hoisting? when we declare any variable or function name. JavaScript makes this declaration top of the scope we call. This system is called as hoisting.

things to know: when we use var keyword we can use it before initialize which was used es5. but in es6 let and const keyword cannot be used before initialize or you will get an error.

2. Block Level Declaration:

In ES6 we use let and const to declare a variable instead of var keyword. var keyword was global usage. that mean if we declarer a variable using var keyword we can use that variable anywhere. but…

The list we are going to learn…

1. Variable (var, let) and const

2. For loop

3. Data types

4. Conditionals (if.. else)

5. DOM

6. Array

7. Object

8. Map, filter, find

9. Function

10. operator

1. Variable and constant

When you are reading this article you probably know about variable and constant. These are the most basic you need to learn JavaScript.

We can declare variable in two way:

1. Using var keyword

2. Using let keyword

There are few differences between var and let. Var is a global variable. The scope of var variable is the full web. we can initialize…

Abdul Basir

Front end web developer. I love to learn and share my learning knowledge with everyone

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