What does it mean for PHP-generated links to have a URL prefix corresponding to my website?

edit

It means that the links generated by your PHP code will have a common prefix in their URL that matches the domain name or hostname of your website. For example, if your website is "www.example.com", the links generated by PHP code will have a prefix that looks like "www.example.com/" followed by the specific path or page name. This helps to ensure that the links are properly formatted and can be easily recognized as belonging to your website. It also helps with SEO and makes it easier for search engines to categorize and index your content.