This is a XML Sitemap which is supposed to be processed by search engines which follow the XML Sitemap standard like Ask.com, Bing, Google and Yahoo.
It was generated using the WordPress content management system and the Google Sitemap Generator Plugin door Arne Brachhold.
You can find more information about XML sitemaps on sitemaps.org and Google's list of sitemap programs.
This file contains links to sub-sitemaps, follow them to see the actual sitemap content.