The DreamKey discs were software used by the Sega Dreamcast in Europe to connect to the internet. They acted as the method of registering online accounts and adjusting settings, as well as accessing the DreamArena service and surf the web (with later discs allowing users to choose their own ISPs). DreamKey discs were distributed with the Dreamcast console - without them, there was no way for the user to register an online account, and therefore no online gaming features could be accessed.