Hello, World! Your First JavaScript Programs

"Hello, World!" is a common phrase used when learning programming languages, often as a beginner's first program. In JavaScript, creating a "Hello, World!" program is straightforward and serves as an introductory example to understand the language's basic syntax.

"Hello, World!" program in JavaScript

Here's a simple example of a "Hello, World!" program in JavaScript:

console.log("Hello, World!");

In this example, the console.log() function is used to display the "Hello, World!" message in the browser's developer console. When you open the browser's developer tools and navigate to the "Console" tab, you'll see the output of this program displayed.

JavaScript within an HTML file

Additionally, you can also use JavaScript to interact with HTML content on a webpage. Here's an example of embedding JavaScript within an HTML file to change the content of an HTML element:

<!DOCTYPE html> <html> <head> <title>Hello, World Example</title> </head> <body> <h1 id="demo">Hello, World!</h1> <script> // JavaScript code document.getElementById("demo").innerHTML = "Hello, JavaScript!"; </script> </body> </html>

In this example, the JavaScript code within the <script> tags selects the HTML element with the id "demo" using the getElementById() method and changes its content using the innerHTML property. When you load this HTML file in a browser, you'll see that the initial "Hello, World!" text gets replaced with "Hello, JavaScript!".


These simple examples demonstrate how JavaScript can be used to output text and manipulate HTML content, forming the foundation for more complex web development tasks.