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In the javascript interview question, there are many important topics which are Null vs Undefined, Double Equal vs Triple Equals, Scope, Block Scope, function Scope, Global variable, Local variable, Closure, etc.

Now I am describing those topics with sort and easy description….

Null Vs Undefined

In javascript, Undefined means a variable has been declared but has not yet been assigned a value, such as


Today I am writing about React js fundamental concept…

What is React js?

React is a javascript “library” and you need to make all decisions by yourself. It is not exactly a “framework”. It focuses on helping you to build user interfaces using components. React is used to put together all the things we can use in the javascript and simplify them so that we can use them easily.

How to install react js?

If you install a react js application you should install this procedure in your terminal code…

Today I discuss some important web design and coding related fundamental concept that helps a web designer or developer to improve his/her coding skills efficiently.

First Concept about cross-browser testing……

1.What is cross-browser testing?

Cross-browser testing is a type of compatibility testing, which ensures that the web sites and web apps you create work across an acceptable number of different web browsers.

2.Why do cross-browser issues occur?

Different web browsers parse websites separately. As a final step in the design, it is important to check your website for any cross-browser compatibility issues. Cross-browser compatibility issues are caused by errors in website code. …

Today I discuss some core concept of javascript

Some important concept of Array

It is used to find an array index number from the array element.



I am a front End web developer.

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