Welcome to the JavaScript fundamentals guide! Whether you're new to programming or just starting with JavaScript, this documentation will help you build a strong foundation. Let's dive into the essentials:

💡 What is JavaScript?

JavaScript is a dynamic programming language used to create interactive web pages. It runs in the browser and allows you to:

  • Manipulate HTML elements
  • Validate forms
  • Create animations
  • Handle user events

🔗 Explore JavaScript in Action

🧰 Core Concepts

Variables

Use let, const, or var to declare variables:

let message = "Hello, world!";
const PI = 3.14;
var count = 10;

📌 Tip: Prefer const for immutable values and let for mutable ones.

Data Types

JavaScript has primitive types like:

  • String 📜
  • Number 🔢
  • Boolean ✅
  • Null 🚫
  • Undefined ❓
  • Symbol 🔐
  • BigInt 🧮

And complex types such as arrays 🧾 and objects 🧳.

Functions

Define functions with:

function greet(name) {
  return "Hello, " + name + "!";
}

Or use arrow functions 🏆:

const greet = (name) => "Hello, " + name + "!";

🚀 Practical Examples

Here's a simple script to show how JavaScript works:

<!DOCTYPE html>
<html>
  <body>
    <p id="demo"></p>
    <script>
      document.getElementById("demo").innerHTML = "JavaScript is awesome!";
    </script>
  </body>
</html>

📚 Next Steps

Ready to level up? Check out our JavaScript Advanced Topics guide for deeper insights into closures, prototypes, and more!

variable_declaration
function_definition