We first discuss the requirements for community information sharing. We then propose an information representation called weak information structures to integrate heterogeneous information such as static information (e.g. local sites information) and dynamic information created in word-of-mouth communication. The weak information structures connects various information media without defining the semantics rigorously. By leaving the interpretation of the semantics to tacit human background knowledge, it becomes compact and robust. We have developed an information sharing system for community called InfoCommon which provides people with intelligent assistance for exchanging and sharing knowledge and ideas. We have evaluated InfoCommon at the ICMAS'96 Mobile Assistant Project.
