With over 15 years developing websites, I‘ve seen firsthand how PHP revolutionized web development. It powers over 75% of all websites, including this blog! Let me explain more about how PHP works and why WordPress relies on it.
PHP (Hypertext Preprocessor) is an open-source scripting language well-suited for web development. Its popularity boomed in the early 2000s.
Today, PHP runs on over 78% of all websites, including WordPress, Facebook, Wikipedia and more. PHP‘s market share is greater than Java, .NET, Python and all other server-side languages combined.
So what makes PHP so popular? Here are some key advantages:
- Beginner-friendly – Easy for new developers to learn compared to C++, Java etc.
- Embeddable – Can be embedded directly into HTML with minimal overhead
- Flexible – Works well for both small and large applications
- Fast performance – PHP code is compiled to optimized bytecode for speed
- Mature ecosystem – Vast libraries, frameworks, CMSes like WordPress and Laravel
- Cross-platform – Runs on Linux, Windows, macOS and more
- Open source – Supported by a large open source community
PHP also integrates well with MySQL and SQL databases. It offers built-in functions for task like:
- String manipulation
- Variables and math operations
- Arrays
- Forms and data handling
- Sessions and cookies
- File I/O operations
- Caching
- APIs and web services
This combination of ease of use, speed, and versatility make PHP extremely well-suited for developing dynamic websites and web applications.
PHP is a server-side scripting language. This means PHP code is executed on the server, then sent to the client.
Here‘s what happens when you visit a PHP website:
- Browser sends request for a page (index.php)
- Web server receives request and passes it to the PHP interpreter
- PHP executes code on the server to generate HTML
- Server sends generated HTML back to the browser
- Browser renders the HTML and displays page
So PHP doesn‘t output anything directly to the browser. It simply generates HTML on the server before passing it along.
For example, say index.php contains both HTML and PHP code:
<html>
<?php
// PHP code to get blog posts
$posts = get_posts();
?>
<body>
<?php
// PHP code to display posts
foreach ($posts as $post) {
echo "<h2>{$post[‘title‘]}</h2>
<p>{$post[‘content‘]}</p>";
}
?>
</body>
</html>The browser would receive pure HTML like this:
<html>
<body>
<h2>Post Title 1</h2>
<p>Post content...</p>
<h2>Post Title 2</h2>
<p>Post content...</p>
</body>
</html>This makes PHP very fast and secure. Code execution and database queries happen on the server, then users simply get plain HTML.
As an open source CMS, WordPress is powered by PHP. Whenever you visit a WordPress site, PHP scripts are executing behind the scenes.
The main PHP files you‘ll find in WordPress include:
- wp-config.php – Configuration settings
- wp-settings.php – Core setup and initialization
- wp-admin/ – Admin panel scripts
- wp-includes/ – Helper functions
- index.php – Main theme file
- header.php – Site header template
- footer.php – Site footer template
- page.php – Page template
- single.php – Single post template
- category.php – Category archive
WordPress PHP scripts connect to the MySQL database to get content like posts, comments, metadata, etc. The scripts assemble these into HTML pages to display to users.
Without PHP, WordPress would need to statically generate pages upfront. It wouldn‘t be able to construct pages dynamically based on user input, comments, new posts etc.
So while PHP may be "behind the scenes", it‘s absolutely critical for WordPress functioning properly.
PHP is actively maintained by a core development team. They release newer versions containing new features, performance improvements, and security fixes.
Key PHP versions:
- PHP 4 – Released in 2000, end of life in 2008
- PHP 5 – Released in 2004, end of life in 2018
- PHP 7 – Released in 2015, end of life in 2021
- PHP 8 – Released in 2020, latest stable version
As of 2024, the current stable versions are PHP 8.1 and PHP 8.0.
WordPress officially requires PHP 7.4 or higher. However, they recommend upgrading to the latest PHP 8.x release for best performance and security.
Generally, you should use the newest PHP version that your web host supports. Reach out to their support team for help upgrading.
Upgrading PHP can provide gains like:
- 2x faster performance on average (from PHP 5.6 to PHP 7.4)
- Improved password hashing and encryption mechanisms
- Just-in-time compilation for faster execution
- Type declarations and strict typing
- Async programming support
- Reduced memory usage
But be sure to test PHP upgrades on staging sites first before deploying to production. Some plugins or themes may be incompatible with bleeding edge versions.
I hope this overview gave you a better idea of how PHP powers WordPress! Let me know if you have any other questions.
