JavaScript Introduction
What is JavaScript?
JavaScript is a high-level, interpreted programming language that is one of the core technologies of the World Wide Web. It enables interactive web pages and is an essential part of web applications.
Fun Fact!
JavaScript was created in just 10 days by Brendan Eich in 1995 while he was working at Netscape.
JavaScript Features:
- Dynamic and interpreted language
- Client-side and server-side programming
- Event-driven programming
- Object-oriented programming support
- Cross-platform compatibility
Your First JavaScript Code
Let's start with the classic "Hello, World!" example:
JavaScript
// This is a comment
console.log("Hello, World!");
// You can also use alert
alert("Welcome to JavaScript!");Code Explanation:
console.log()- Prints output to the browser consolealert()- Shows a popup dialog box//- Single-line comment- Semicolons (;) are used to end statements
Where to Write JavaScript
JavaScript can be included in HTML documents in several ways:
1. Inline JavaScript
HTML
<button onclick="alert('Button clicked!')">Click Me</button>2. Internal JavaScript
HTML
<script>
function greetUser() {
alert("Hello from JavaScript!");
}
</script>3. External JavaScript
HTML
<script src="script.js"></script>Interactive JavaScript Console
Try JavaScript code in real-time:
Click "Run Code" to see output here...