How can PHP be used to include the content of a text file in an HTML document for a text scroller?

To include the content of a text file in an HTML document for a text scroller using PHP, you can use the `file_get_contents()` function to read the contents of the text file and then echo it within the HTML document where you want the text to appear. This allows you to dynamically include the text file content in your HTML without having to hardcode it.

<?php
$text = file_get_contents('your_text_file.txt');
echo '<marquee>' . $text . '</marquee>';
?>