PHP Tutorial: Introduction
PHP is an acronym for "Hypertext Preprocessor." It is a widely-used, open-source scripting language executed on the server. If you want to build dynamic, data-driven, and interactive websites, learning PHP is the industry-standard choice.
1. What is PHP?
- PHP is a Server-Side language, meaning the code is executed on the server, and the client (browser) receives plain HTML.
- It is powerful enough to be at the core of the biggest blogging system on the web (WordPress).
- It is deep enough to run the largest social network (Facebook).
- It is also easy enough to be a beginner's first server-side language!
2. What Can PHP Do?
PHP is much more than just a tool to display text; it provides the "logic" for your web applications:
- Dynamic Page Content: Generate web pages on the fly based on user input or database records.
- File Handling: Create, open, read, write, upload, and close files on the server.
- Form Data Collection: Gather data from users through HTML forms (like Contact or Sign-up forms).
- Cookies & Sessions: Send and receive cookies to identify users and track their activity across pages.
- Database Interaction: Add, delete, and modify data in databases like MySQL, PostgreSQL, and Oracle.
- Access Control: Restrict users from accessing specific pages or parts of your website.
- Data Encryption: Encrypt sensitive data for secure transmission over the internet.
3. Why Use PHP in 2026?
- Platform Independent: PHP runs on various platforms (Windows, Linux, Unix, macOS, etc.).
- High Compatibility: It is compatible with almost all servers used today (Apache, Nginx, IIS).
- Ease of Learning: PHP has a logical syntax that is easy for those coming from a C or Java background.
- Large Community: With millions of developers worldwide, you can find ready-made scripts and support for almost any task.
- Performance: Modern PHP (version 8.x+) is highly optimized and much faster than previous versions.
4. Basic PHP Syntax
A PHP script can be placed anywhere in the document. It starts with <?php and ends with ?>. Every statement must end with a semicolon (;).
<?php
// This is a single-line comment
/* This is a
multi-line comment */
echo "
Welcome to PHP!
";
$version = 8.3;
echo "You are learning PHP version " . $version;
?>
5. How PHP Works on the Server
When a user visits a PHP page, the server processes the PHP code, interacts with any necessary databases, and then sends a pure HTML file back to the browser. The user never sees the actual PHP source code.
Important: PHP files have the extension .php. To run these files, you must have a local server installed, such as XAMPP or WAMP.