What Is PHP?
PHP (originally 'Personal Home Page Tools', now a recursive backronym for 'PHP: Hypertext Preprocessor') is an open-source, server-side scripting language created by Rasmus Lerdorf in 1994 and formalized as a language with the Zend Engine in PHP 4 (2000). Unlike client-side JavaScript, PHP code runs entirely on the web server: a client requests a page, the PHP interpreter executes the script, generates HTML (or JSON, XML, binary data, etc.), and only that output is sent to the browser. This model made PHP the natural choice for dynamic, database-backed websites in the late 1990s and early 2000s, and it remains the engine behind WordPress, large parts of Facebook's original stack (via HHVM), Wikipedia, Slack's early backend, and countless e-commerce platforms like Magento and WooCommerce.
Cricket analogy: PHP was created by Rasmus Lerdorf in 1994 like a young cricketer starting in club cricket, formalized into a serious engine with PHP 4's Zend Engine in 2000 like graduating to international cricket; unlike a batter facing the ball live in front of the crowd (client-side JavaScript), PHP works entirely in the dressing room preparing strategy (server-side) before only the resulting scorecard reaches the stands, which is why it became the backbone powering giants like WordPress and Wikipedia.
How a PHP Request Is Processed
When a browser requests a .php file, the web server (commonly Apache with mod_php, or Nginx with PHP-FPM as a FastCGI process manager) hands the file to the PHP interpreter. The interpreter parses the script top to bottom, executing any code between <?php and ?> tags while passing everything else through as literal text. Because this all happens before the response leaves the server, the client never sees your PHP source, your database credentials, or your business logic — only the resulting markup or data.
Cricket analogy: When a fan requests a live-score page, it's like the ground's scoring office (Apache/Nginx) handing the raw notes to a scorer (PHP interpreter) who reads top to bottom, converting only the marked calculation sections into a public scoreboard update while leaving the rest as-is; the fan never sees the scorer's private notes, the team's internal strategy sheet, or player fitness data — only the final scoreboard number.
<?php
// hello.php — a minimal PHP script mixing PHP with HTML
$name = $_GET['name'] ?? 'World';
?>
<!DOCTYPE html>
<html>
<body>
<h1>Hello, <?= htmlspecialchars($name) ?>!</h1>
<p>Generated at <?= date('Y-m-d H:i:s') ?> on the server.</p>
</body>
</html>
Why PHP Still Matters in 2026
Modern PHP (8.0 through 8.4) bears little resemblance to the loosely-typed PHP 4/5 scripts of the mid-2000s. It has a JIT compiler, strict typing, enums, readonly properties, fibers for cooperative concurrency, and a mature package ecosystem via Composer and Packagist. Frameworks such as Laravel and Symfony bring dependency injection, ORM layers, and testing tooling comparable to any modern backend stack. PHP powers roughly 75% of websites whose server-side language is known, which means enormous existing codebases, a deep hiring pool, and battle-tested deployment patterns.
Cricket analogy: Modern PHP (8.0-8.4) is as different from PHP 4/5 as today's data-driven, DRS-equipped cricket is from the loosely-officiated matches of the 1990s — new tools like a JIT-compiled bowling machine (JIT compiler), strict LBW-review rules (strict typing), and fixed dismissal categories (enums); frameworks like Laravel and Symfony bring a full analytics and fielding-coach setup, and with PHP powering roughly 75% of the sport's global infrastructure, there's a deep pool of experienced players and well-tested conditions.
PHP is 'shared-nothing' by default: each incoming request gets a fresh interpreter state, with no memory shared between requests unless you explicitly use a cache like Redis, APCu, or a database. This simplifies reasoning about concurrency but means you must persist state deliberately.
Do not confuse the 'PHP version installed on your machine' with the 'PHP version your production server runs.' Language features like enums (8.1+) or readonly properties (8.1+) will cause a fatal parse error on older interpreters, so always check your host's PHP version before relying on new syntax.
- PHP is a server-side scripting language: code executes on the server and only output is sent to the client.
- PHP was created in 1994 by Rasmus Lerdorf and has been continuously developed since, now on the PHP 8.x series.
- Common deployment stacks pair PHP-FPM with Nginx, or mod_php with Apache.
- Major platforms like WordPress, Wikipedia, and Laravel/Symfony-based apps run on PHP.
- Modern PHP includes strict types, enums, JIT compilation, and a rich Composer package ecosystem.
- Each PHP request is independent by default (shared-nothing architecture) unless you add external state like a cache.
Practice what you learned
1. Where does PHP code execute?
2. Which component commonly processes PHP requests when paired with Nginx?
3. What does 'shared-nothing' mean in PHP's default execution model?
4. Who originally created PHP?
5. Which of these is a genuinely modern (PHP 8.1+) language feature?
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