1. Introduction to PHP

What is PHP?

• Definition: PHP (Hypertext Preprocessor) is a server-side scripting language designed for web development. It is executed on the server, and the result is sent to the client (browser) as plain HTML.
• Explanation: PHP allows you to create dynamic web pages that can interact with databases, handle forms, manage sessions, and more. Unlike static HTML, PHP enables you to generate content dynamically based on user input or other conditions.
• How to Use: PHP scripts are embedded within HTML files using <?php ... ?> tags. The server processes the PHP code and sends the output (HTML, CSS, JavaScript, etc.) to the browser.

Why Learn PHP?

• Definition: PHP is one of the most popular server-side languages due to its ease of use, flexibility, and widespread adoption in web development.
• Explanation: PHP is used by millions of websites, including major platforms like WordPress, Facebook (initially), and Wikipedia. It integrates seamlessly with HTML and supports multiple databases, making it ideal for building dynamic websites.
• How to Use: You can use PHP to build anything from simple contact forms to complex e-commerce platforms. Its versatility makes it a great choice for both beginners and experienced developers.

Basic Syntax

• Definition: PHP syntax refers to the rules and structure of writing PHP code.
• Explanation: PHP code starts with <?php and ends with ?>. Each statement must end with a semicolon (;). PHP is case-sensitive for variable names but not for functions or keywords.
• How to Use:

<?php
// This is a comment
echo "Hello, World!"; // Outputs: Hello, World!
?>

2. Setting Up Your Environment

Requirements

• Definition: To run PHP scripts, you need a web server, PHP interpreter, and optionally a database system.
• Explanation: PHP scripts are executed on a server, so you need a local or remote server environment. Tools like XAMPP or MAMP bundle Apache (web server), MySQL (database), and PHP into a single package for easy setup.
• How to Use:
  • Install XAMPP or MAMP.
  • Place your PHP files in the htdocs (XAMPP) or MAMP folder.
  • Access your PHP files via http://localhost/yourfile.php.