What is the correct way to combine HTML and PHP codes in a PHP file?

When combining HTML and PHP codes in a PHP file, you can simply embed PHP code within your HTML by using `<?php ?>` tags. This allows you to dynamically generate HTML content using PHP. Make sure to save the file with a `.php` extension to ensure that the PHP code is processed by the server.

&lt;!DOCTYPE html&gt;
&lt;html&gt;
&lt;head&gt;
    &lt;title&gt;PHP and HTML&lt;/title&gt;
&lt;/head&gt;
&lt;body&gt;
    &lt;h1&gt;&lt;?php echo &quot;Hello, World!&quot;; ?&gt;&lt;/h1&gt;
&lt;/body&gt;
&lt;/html&gt;