Portals are Internet applications that allow central access to user-specific content. They often serve as a starting point for the Internet and offer the user all relevant information at a glance. Vertical portals, also called vortals, are vertical portals that refer to industry-specific topics, e.g. only to the medical or only to the media industry. They bundle all necessary applications such as information search, purchase, etc. for the specific industry. Accordingly, vertical portals are also frequently linked to vertical e-markets, vertical electronic marketplaces (EM).