Sometimes the address of a website ends in “php,” e.g., index.php. When you see that, you know it was written in PHP. But what exactly does that mean?

HTML is the language of the Web. A page written in HTML is the same every time it’s called up. It might have JavaScript to customize its behavior in the browser, but what it gets from the server never changes. HTML is a markup language, controlling the presentation. PHP is a programming language, controlling the content and letting it change as needed.

PHP is specifically designed for the Web. When a browser calls up a PHP page, its code runs on the server and delivers HTML to the browser. It can do things like looking up information on a database or checking whether the user is logged in. The PHP code never appears in the browser.

PHP is fully open source, and it’s available for any computer and operating system. It never has any surprise licensing fees, unlike languages supported by commercial vendors. It gets regular updates, and there is a huge amount of third-party code to help developers.

A typical PHP page is a mix of PHP and HTML. The parts of the page that don’t change are in HTML, and the PHP fills in the parts that the page needs to generate on the fly. The ability to do this sets PHP apart from languages that weren’t designed for the Web. Other languages, like Java, are used to create Web pages, but the process takes more steps and is often harder to maintain.

WordPress, which is the basis of millions of websites, is written in PHP. Every page, post, and plugin is delivered by PHP code. Unidad22 provides expert PHP Web development. Contact us to learn how we can help you build the best site for your business.