What is JavaScript? A Beginner’s Guide

#webdev #javascript #beginners

If you've ever interacted with a website—clicked a button, filled out a form, or watched a video—chances are JavaScript was involved. It’s the language that brings websites to life.

What is JavaScript?

JavaScript (JS) is a programming language that allows you to create dynamic, interactive content on the web. It runs in your browser and is used by nearly every modern website.

Where Does JavaScript Run?

Originally designed to run in web browsers, JavaScript can now also run on servers using environments like Node.js. This means JavaScript can build both frontend and backend apps.

Why JavaScript Matters

Supported by all browsers
Massive ecosystem (React, Vue, Node, etc.)
Easy to start with, powerful as you grow

Real-World Examples

Updating content without refreshing the page (AJAX)
Interactive forms and validation
Slideshows and image galleries
Chat apps and games

How JavaScript Fits Into Web Development

Web development has 3 core layers:

HTML – structure
CSS – style
JavaScript – behavior

Your First JavaScript Code

`<!DOCTYPE html>
<html>
  <body>
    <h1>Hello from JavaScript</h1>
    <button onclick="sayHello()">Click Me</button>

    <script>
      function sayHello() {
        alert("Hello, world!");
      }
    </script>
  </body>
</html>`

What to Learn Next
Variables (let, const, var)

Functions and scope

Loops and conditionals

Arrays and objects

Conclusion
JavaScript is the language of the web—and now more powerful than ever. Whether you're building websites, games, or mobile apps, learning JavaScript opens up endless possibilities.