High Quality Content by WIKIPEDIA articles! DansGuardian, written by SmoothWall Ltd and others, is content-control software: software designed to control which websites users can access. It also includes virus filtering and usage monitoring features. DansGuardian must be installed on a Unix or GNU/Linux computer, such as a server computer; its filtering extends to all computers in an organization, including Windows and Macintosh computers. DansGuardian is used by schools, businesses, value-added Internet service providers, and others.