PHP stands for "PHP: Hypertext Preprocessor" (a recursive acronym). It is an open-source, server-side scripting language designed primarily for web development, though it can also be used for general-purpose programming.
Here are the key things to know about it:
What it does
Runs on the server: PHP code is executed on the web server. The server processes the script and sends the resulting output—usually HTML, but also JSON, images, or PDFs—to the user's browser.
Generates dynamic content: Instead of serving static HTML files, PHP can build pages on the fly based on database queries, user logins, form submissions, time of day, etc.
Key characteristics
Embedded in HTML: You can mix PHP code directly into HTML files using <?php ... ?> tags.
Interpreted: It doesn't need to be compiled beforehand; the server reads and executes the code as requested.
Cross-platform: Works on Windows, Linux, macOS, and most web servers (especially Apache and Nginx).
Large ecosystem: Huge libraries, frameworks (Laravel, Symfony), and content management systems (WordPress, Drupal, Joomla).
Common uses
Building websites and web applications
Content Management Systems (CMS) — WordPress alone powers over 40% of the web
E-commerce platforms (Magento, WooCommerce)
APIs and backend services
Command-line scripting (CLI)
Brief history
Created by Rasmus Lerdorf in 1994, it started as a set of tools for tracking visitors to his online resume ("Personal Home Page Tools"). It evolved into a full programming language, with modern versions (PHP 8.x) offering strong typing, performance improvements, and modern language features.
Despite frequent debates about its popularity relative to newer languages, PHP remains one of the most widely used server-side technologies on the internet.