A domain alias or domain parking is the act of placing additional domain names in a limited Virtual Server. This domain would then point to the IP of the top level domain. Traffic will be automatically forwarded.
Your main web application address is xyz.com but you have also registered xyz.net and xyz.org. You can use domain parking to point the “.net” and “.org” to the xyz.com at the DNS level.
Your web presence is written in multiple languages (English = Main Application - German, Frence, and Italian) and is controlled from a central CMS system. This xyz.com site holds your English, German, Frence, and Italian Content.
Parking xyz.de / xyz.fr / xyz.it and using a rewrite can separate each language to its Regional TDL URL.