PHP HTML output from web server


Example

PHP can be used to add content to HTML files. While HTML is processed directly by a web browser, PHP scripts are executed by a web server and the resulting HTML is sent to the browser.

The following HTML markup contains a PHP statement that will add Hello World! to the output:

<!DOCTYPE html>
<html>
    <head>
        <title>PHP!</title>
    </head>
    <body>
        <p><?php echo "Hello world!"; ?></p>
    </body>
</html>

When this is saved as a PHP script and executed by a web server, the following HTML will be sent to the user's browser:

<!DOCTYPE html>
<html>
    <head>
        <title>PHP!</title>
    </head>
    <body>
        <p>Hello world!</p>
    </body>
</html>
PHP 5.x5.4

echo also has a shortcut syntax, which lets you immediately print a value. Prior to PHP 5.4.0, this short syntax only works with the short_open_tag configuration setting enabled.

For example, consider the following code:

<p><?= "Hello world!" ?></p>

Its output is identical to the output of the following:

<p><?php echo "Hello world!"; ?></p>

In real-world applications, all data output by PHP to an HTML page should be properly escaped to prevent XSS (Cross-site scripting) attacks or text corruption.

See also: Strings and PSR-1, which describes best practices, including the proper use of short tags (<?= ... ?>).