The cyber world or cyber society in future is firstly discussed with respect to its significance, the infrastructure of such world, plausible configuration of cyber society which comprises an information community place of virtual school, library, factories, offices, communities and homes, etc., connected via information highway, and the people¡Çs lifestyle there. Then, human interface, virtual reality and agent are discussed as the key technologies for realizing cyber society. Lastly an interface agent of virtual collaborator is proposed as a humanized intelligent interface agent system for helping the operation and maintenance task in automated plant in future.