PHP is a programming language. It’s a pretty widely used language and can be embedded into HTML. PHP is a server-side language. When a user requests a web page that contains PHP code, the code is processed by the PHP module installed on that web server. The PHP pre-processor then generates HTML output to be displayed on the user’s browser screen.
Example of a simple PHP code:
<?php echo "Hello, World!"; ?>
PHP files usually have a .php extension. PHP can be used inside HTML documents. The PHP pre-processor only processes code inside the php opening tag <?php and the closing tag ?>.
Example of PHP code inside an HTML document:
<html>
<head>
<title><?php bloginfo('name'); ?></title>
</head>