JavaScript

JavaScript: The dynamic language of the web.

JavaScript is a programming language that brings web pages to life. It's the core technology of the web, working alongside HTML and CSS. While HTML structures the content and CSS styles it. JavaScript adds interactivity and dynamic behaviour.

What can we do with JavaScript ?

Create interactive elements: buttons, menus, sliders, etc.
Animate graphics and images: Create engaging visual effects.
Update content dynamically: Load new data without reloading the page.
Build web applications: Complex applications like online stores, social media platforms.
Develop server side applications: Using Node.js, you can create backend systems.

Key characterstics of JavaScript

Lightweight and Interpreted: It runs directly in the browser without needing compilation.
Cross-Platform: Works on different operating systems and browsers.
Object-Oriented: Supports object-based programming for code organization.
Dynamically types: You don't need to specify data types beforehand.

History of JavaScript

Birth of JavaScript

1995Brenden Eich, a programmer at Netscape Communication, created JavaScript in a mere 10 days. Initially named Mocha, it was later renamed LiveScript and finally JavaScript to capitalize on the popularity of Java at the time.
PurposeDesigned to add interactivity to static HTML pages, JavaScript brought life to the web.

Early years and Browser's war

1996 - 1997JavaScript gained rapid adoption with Netscape Navigator and Internet Explorer becoming the dominant browsers.
Browser warsIntense competiton between Netscape and Microsoft led to different JavaScript implementations, causing compatiblity issues.
ECMAScriptTo standardize the language, ECMA International created ECMAScript, a specification for JavaScript.

Growth and Maturity

1997 - 2000The Document Object Model ( DOM ) and Dynamic HTML ( DHTML ) emerged, expanding JavaScript capablities.
2006 - 2010jquery and other libraries simplified JavaScript development and popularized its use.
2009 - 2015ECMAScript 5 and 6 introduced significant improvements, making JavaScript a more robust language.

Modern JavaScript

2015 onwardsJavaScript has evolved rapidly, becoming a full-fledge language for building complex applications.
Node.jsRevolutionized server-side development with JavaScript, enabling full stack development.
Frameworks and LibrariesReact, Angular, Vue, and others emerged, providing powerful tools for building user interfaces.

Creation of server-side JavaScript

While JavaScript initially designed for the client-side, its versatility and popularity led to its expansion into server-side development.

Early attempts

Before Node.jsSeveral attempts were made to run JavaScript on the server, but they lacked widespread adoption.
ChallengesPerformance, scalablity, and ecosystem limitations hindered these early efforts.

The rise of Node.js

2009Ryan Dahl released Node.js, a JavaScript runtime built on chrome's V8 Javascript engine.
Event-driven architectureNode.js's non-blocking, event-driven approach made it highly efficient for handling concurrent connections.
Package ecosystem ( npm )A vast collection of reusable modules accelerated development.
Full-Stack JavaScriptDevelopers could now use JavaScript for both front-end and back-end development.

Impact of Node.js

Rapid growthNode.js gained immense popularity, becoming a preferred choice for server-side development
Diverse applicationUsed for web servers, real-time applications, APIs, and more.
Ecosystem expansionA thriving ecosystem of frameworks, libraries, and tools emerged.

Beyond Node.js

Other optionsWhile Node.js dominates the server-side JavaScript landscape, alternatives like Deno have emerged.
Continued evolutionJavaScript and Node.js are constantly evolving, with new features and improvements enhancing their capablities.

You have to know!

What is the difference between a normal text file and a source code file ?

Lets create a file as test.js

console.log("vikash");

Inside the test.js file we have console.log("vikash") and each word has specific task or meaning on the programming. console does a specific task when the source code executed on the software.

Lets create another file as test.txt

console.log("vikash")

But the main thing, which file can be executed, when we inject them into a software ( compiler/interpreter ). This software has a task to identify the extension of file and perform actions according to the written source code.

Every programming language has a syntax to write their source code and every programming language comes with their extension. eg. .js, .java, .cpp, .py and so on..

Old style vs New style of learning JavaScript

In early days, People runs script using a HTML file. They just simply create an index.html file and inside it they start a <script> tag for writing Javascript.

<!DOCTYPE html>
<html lang="en">
  <head>
    <title>Document</title>
  </head>
  <body>
    <script>
      console.log("Hello world!");
    </script>
  </body>
</html>

and executes the HTML file on the browser. Because JavaScript is hidden inside for a long time in the browser.

But in the recent past It emerged from the browser by Ryan Dahl.

Nowadays, we can execute our JavaScript code standalone like python, java, c++ code.

Lets talk about PC configuration and Softwares to run JavaScript

For running JavaScript, There is no any higher requirement. We can run our code directly on the browser.

Directly on browser's console
Install a runtime for JavaScript like node.js Once you download and installing, confirm it.
```
node -v
```
Install a code editor ( IDE ) like vs code VS code is an IDE ( Integrated Development Environment ) provides multiple features like auto indentation, code suggestion, Extension supports, File tracking using git and GitHub, Integrated Terminal.

Run your first JavaScript file

Create a directory where you want to store your JavaScript file, open it in vs code.

Lets create a file as test.js and write some code

// test.js

console.log("hello world!");

Now look on the top of the vs code you will find Terminal, create a new terminal and execute the source file

node test.js

JavaScript Basics