1. An information sharing system, comprising: an information management system that provides user assistance for interacting with the system; a shared information repository having electronic files that are categorized according to an ontology; a repository of categorization rules which are used by the information management system for automatically categorizing an electronic file to be stored in the shared information repository; and a learning engine that automatically generates or updates categorization rules in the repository of categorization rules based on knowledge obtained from multi-user interactions with the system; wherein the information management system provides user assistance in storing an electronic file in the shared information repository under one or more ontological categories that are user-specified or ontological categories that are suggested by the information management system.