React is an open-source javascript library. It first released on May 29, 2013. There is a big question about React that, is it Library or Framework. For getting this answer, you need to know about what is framework. A framework is a prebuilt structure. For starting with a framework you don’t need to include anything. For a startup team, it will be a good solution, because everything is optimized there. Also, you need to code in a particular way.

But in React you need to use a different library for a particular task. It is a good solution for building…

What is different between null and undefined?

When we write a variable but didn’t set any value to the variable we will get an “undefined” value. The reason is we define the variable but didn’t set a value for it. There is several ways to get a value undefined, if we wrote an object and then try to access its property that is not available in an object we will get “undefined”.
Null means that nothing existing inside it. If you want to check that, is there anything that exists inside a variable or function, you can check it with “null”.

What is the difference between double(==) and triple(===) equal?

For getting a better understanding between…

Types Of Values

In Javascript, there are two types of values. One is primitive values such as Number, String, Undefined, Null, Symbol, BigInts. Other types of values in objects and functions. These are the two types of values that existed in javascript.


When we start coding we always made mistakes to write code and for this reason, our code immediately stops working. For handling this type of error javascript has “try…catch” syntax. Inside of “try”, all code will be going on. and if any error occurred in code then “try” will stop working and catch start working. The catch will wrap all…

Javascript has lots of core concepts. Here I will discuss some core concepts. Javascript has 8 types. Types are:

  1. String
  2. Number
  3. Boolean
  4. Symbol
  5. Objects (inside: 1. Functions 2. array 3. Date 4. RegExp)
  6. null
  7. undefined
  8. Error

These are the types of javascript. Here I will try to describe Array, Number, String, and Math.


The array is an exceptional type of object in JavaScript. It declares with [] brackets. It has lots of methods. Here some examples:

1. Concat()

This method basically used for merging two or more arrays in one. …

Numan Ahmed

I’m passionate & creative about web design & development with problem-solving skills.

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