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Difference between NULL and Undefined

In JavaScript, Null means, there is nothing exist. Like space. No data type of NULL exist also. But, for undefined, it is not completely nothing. That means, it is declared but yet it is not defined. So, an undefined variable has a data type like integer, float, string, function or object which is not defined yet. But after definition, it won’t show error.

Double Equal (==) vs Triple Equal

‘=’ is an assignment operator. It will assign the value of right side to the left side. But when it came to ‘==’, it means to compare value of both side. …


Is React.js framework or library ? What do you think?
React.js is actually a JavaScript library. And can also add more library if needed.

React tree reconciliation

We know that react is faster than other library or framework. But how? Because, react uses reconciliation tree and it doesn’t change full pages or load entire pages. Instead of doing reload or change, it updates DOM. When a component’s change, react calculate if it necessary to update or change the DOM. That’s how react tree reconciliation works.

JSX

JSX is an HTML like syntax extension used by React that extends ECMAScript so that HTML like text…


JavaScript Expression
In JavaScript, expression is any valid piece of code that can generate value (like numeric, string, bool etc.)
According to MDN, there are different types of JavaScript expression. They are : a) Arithmetic b)String c)Logical d)Primary e)Left-hand-side

few examples of expressions in JavaScript

JavaScript Objects
JavaScript object is one kind of data types in JavaScript. It can construct with various collection of variables, function or objects.


Ever heard about programming language? Maybe yes.
What do you know about programming language? Is it only build with ‘0’ and ‘1’ ?

Actually yes ! Programming language is build with ‘0’ and ‘1’. Then,
=> Why this programming language looks like human language?
=> How it processed and work with 0 and 1 ?

Why it is not 0 and 1 ?
Why it is not 0 and 1 ?

Can your read the text inside the image?
Yes! You can. But I already said programming language build with 0 and 1.

Actually this programming language is evaluated from machine language which is consist with 0 and 1. After so many years of experiment and…

SAJID

Enthusiastic react developer

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