What is JavaScript?

• JavaScript is a lightweight, OOP language.
• It is a scripting language for web pages.
• It is used to add interactivity and dynamic effects to web pages.
• “.js” is the extension.
• Nowadays used in server-side development.
• JS Frontend Frameworks: React, Angular, Vue.
• JS Backend Frameworks: Express, Node.

How to execute JavaScript?

JavaScript can be executed right inside one’s browser. You can open the JS console and start writing JS there.
Another way to execute JS is a runtime like Node.js which can be installed and used to run JavaScript code.
Yet another way to execute JavaScript is by inserting it inside the <script> tag of an HTML document.

Getting Started with JavaScript

To start using JavaScript, you'll need a text editor and a web browser. There are many text editors available, such as Sublime Text, Atom, and Visual Studio Code, which are all popular choices among developers.
Once you have a text editor set up, you can start writing JavaScript code. To do this, you'll need to create a new file with a .js extension and then type your code into the file. You can then save the file and open it in your web browser to see the results.

How to use JavaScript

Variables in JavaScript

What are Variables?

In JavaScript, variables are used to store data. They are an essential part of any programming language, as they allow you to store, retrieve, and manipulate data in your programs.
There are a few different ways to declare variables in JavaScript, each with its own syntax and rules. In this blog post, we'll take a look at the different types of variables available in JavaScript and how to use them.

Declaring Variables

To declare a variable in JavaScript, you use the "var" keyword followed by the name of the variable. For example:

Data Types

In JavaScript, there are several data types that you can use to store different types of data. Some common data types include:

• Numbers (e.g. 10, 3.14)
• Strings (e.g. "hello", 'world')
• Booleans (e.g. true, false)
• Arrays (e.g. [1, 2, 3])
• Objects (e.g. { name: "John", age: 30 })

JavaScript Basics

• If else conditionals
• If else ladder
• Switch case
• Ternary Operator
• For Loops
• While Loop
• Functions

JavaScript Objects

• Strings
• Arrays
• Methods
• Loops with Arrays
• Map, Filter and Reduce
• Date
• Math
• Number
• Boolean

Document Object Model

• Window Object
• Document Object
• getElementbyId
• getElementsByClassName
• getElementsByName
• getElementsByTagName
• innerHTML
• outerHTML

OOPS in JavaScript

• Class
• Objects
• Constructor
• Static Method
• Encapsulation
• Inheritance
• Polymorphism
• Abstraction