PHP Hello World: Your First Script

Today, we'll guide you through creating and running your first PHP script. The "Hello World" program is a classic beginner's exercise in many programming languages, and PHP is no exception. Let's dive in!

What is PHP?

PHP (Hypertext Preprocessor) is a popular server-side scripting language designed for web development. It is embedded within HTML and executed on the server, producing dynamic web pages.

Prerequisites

Before we start, make sure you have your PHP development environment set up. If you haven't done this yet, follow our guide from the Installation Blog to install and configure XAMPP.

Writing Your First PHP Script

We'll create a simple PHP file that outputs "Hello World!" to the browser.

1. Create a PHP File:

Open the htdocs directory within your XAMPP installation. The default path is:
- Windows: C:\xampp\htdocs
- macOS: /Applications/XAMPP/htdocs
Create a new folder named hello_world.
Inside the hello_world folder, create a new file named index.php.

2. Write the PHP Code:

Open index.php with your preferred text editor or IDE (like Visual Studio Code, Sublime Text, or Notepad++).
Add the following code to index.php:

<?php
    echo "Hello, World!";
?>

Explanation:

<?php: This tag starts the PHP code block.
echo "Hello, World!";: This command outputs the string "Hello, World!" to the browser.
?>: This tag ends the PHP code block. It's optional if your PHP script is the only thing in the file.

3. Run Your PHP Script:

Open your web browser and type http://localhost/hello_world/index.php in the address bar.
You should see the message "Hello, World!" displayed on the page.

Understanding the PHP Syntax

PHP syntax is straightforward and easy to learn. Here's a breakdown of what you've written:

PHP Tags:<?php and ?> are used to indicate the start and end of PHP code.
Echo Statement:echo is a PHP statement used to output text or variables to the browser.
Semicolon: Each PHP statement must end with a semicolon (;).

Embedding PHP in HTML

One of PHP's strengths is its ability to be embedded within HTML. Let's enhance our script by adding some HTML code.

1. Updateindex.php:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Hello World</title>
</head>
<body>
    <h1><?php echo "Hello, World!"; ?></h1>
</body>
</html>

Explanation:

The HTML structure includes the DOCTYPE, html, head, and body tags.
PHP is embedded within the <h1> tag, demonstrating how PHP can be used to dynamically generate HTML content.

2. Run the Updated Script:

Refresh your browser to see the updated page with "Hello, World!" displayed as an <h1> heading.

PHP Comments

Comments are essential for documenting your code. PHP supports both single-line and multi-line comments.

1. Single-Line Comment:

// This is a single-line comment
echo "Hello, World!";

2. Multi-Line Comment:

/*
 This is a multi-line comment
 that spans multiple lines.
*/
echo "Hello, World!";

Comments are ignored by the PHP interpreter and are useful for explaining your code to others (or to yourself).

Conclusion

Congratulations! You've written and run your first PHP script. Today, you learned how to create a PHP file, write basic PHP code, embed PHP in HTML, and use comments. These fundamentals are the building blocks for more complex PHP applications.

Your First PHP Script: Hello World!