Univention Corporate Server (UCS) is a server operating system derived from Debian GNU/Linux with an integrated management system for the central and cross-platform administration of servers, services, clients, desktops and users as well as virtualized computers operated in UCS. Since UCS 4.0 virtual machines can be managed on local servers and on cloud platforms, which are based on OpenStack and Amazon EC2.[2] Univention also supports the functions provided in many companies by Microsoft Active Directory for the administration of computers operated with Microsoft Windows[3][4] via the integration of the open source software Samba 4. Since UCS 3.1, UCS-based components and established third party products, which are certified for UCS, can be installed and integrated via the Univention App Center. Since UCS 4.0-2, also Docker containers can be run on UCS systems.[5]