How can the include command be used to include content in a webpage in PHP?

To include content in a webpage in PHP, you can use the `include` command followed by the file path of the content you want to include. This allows you to reuse code across multiple pages and keep your code organized.

<?php
include 'header.php'; // include header content
include 'sidebar.php'; // include sidebar content
include 'footer.php'; // include footer content
?>