Truthy and Falsy values

True and false values for different variable depending on condition,

Number:

String:

Array:

object:

Undefined:

  • if a variable value is undefined then JS will consider the variable as false.

React.JS Fundamentals

React is a javascript library and helps in building user interfaces(UI). “React is declarative” — programmers just need to describe what type of UI they want React will understand declarative descriptions and take care of how to do it and what will be the actual UI that needs to show in the browser with dynamic data. DOM(Document Object Model) a tree structure that was introduced by javascript and fall web work slow, the improved version Virtual DOM was introduced by React that work the same like DOM but faster the web work for this react said to as a game-changer…


Type of value in JavaScript

Javascript has 2 categories for values:

  • primitive value: the value which does not have any method or not an object. Which are used for math calculations(-15, 4, 9.8), for text(‘hello’), for adding unique property keys to an object(Unusual), for logical operation(true, false), for math on big numbers(new and Unusual), for unintentionally missing values, for intentionally missing values. example: number, string, symbol, boolean, bigInt, undefined, and null
  • objects, and functions: object({}) is a collection of properties that includes key and values and used to group related data and code. …

Figure: Javascript

What is javascript, key features of javascript:

1. Interpreted or just-in-time (almost immediately) compiled programming language[not exactly compiled language it means JS need not convert in the machine-readable language(where machine only can read 0 and 1) and then run it].

2. The first-class function can implement anything with its functions.

3. In the beginning, javaScript use only for the client-side, the browser.

4. Later, javaScript modified for server-side use, also with help of Node.js. where Node.js is not a programming language. An open-source, cross-platform.

JavaScript is a client-side(front-end) language but by using a special way we can run…

MD. Ehsanul Haque

I’m a junior front-end web developer.

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