"I am Saqib Jahangir. A passionate vlogger, software engineer, trainer and avid traveler with a deep love for exploring the hidden gems of our beautiful planet. With a strong foundation in Application Development, Application Architecture & Database Design and Product Management, I bring over a decade of hands-on experience building secure, scalable, and resilient web applications for a diverse range of industries."

Introduction to JavaScript

 

JavaScript is a powerful, versatile programming language primarily used to add interactivity and dynamic behavior to websites. Unlike HTML and CSS, which structure and style content, JavaScript lets you manipulate webpage elements, respond to user actions, and even communicate with servers.

It runs directly in the browser, making it an essential part of modern web development.

Role of JavaScript in Web Development (HTML + CSS + JS)

Web development typically involves three core technologies:

·         HTML (HyperText Markup Language): Structures the content on the page, like headings, paragraphs, images, and links.

·         CSS (Cascading Style Sheets): Styles the content, controlling colors, fonts, layouts, and responsiveness.

·         JavaScript: Adds behavior and interactivity — for example, form validation, animations, content updates without reloading, and much more.

Together, these three create the complete user experience on the web: HTML builds the skeleton, CSS dresses it up, and JavaScript brings it to life.

Writing JavaScript: Inline, Internal, External

You can add JavaScript to your webpages in three ways:

1.      Inline JavaScript
JavaScript code written directly inside HTML elements, usually within event attributes like onclick.

<button onclick="alert('Hello!')">Click Me</button>

Note: Inline scripts are simple but generally discouraged for larger projects due to maintainability and separation of concerns.

2.      Internal JavaScript
JavaScript code placed inside a <script> tag within the HTML document, usually inside the <head> or at the end of the <body>.

<script>
  function greet() {
    alert('Welcome!');
  }
</script>
 
<button onclick="greet()">Click Me</button>

3.      External JavaScript
JavaScript code written in separate .js files and linked to your HTML using the <script> tag with a src attribute.

<script src="script.js"></script>

This method is preferred for larger projects because it keeps HTML and JavaScript separate, improving organization and reusability.

 

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