This book provides an overview of interfaces to social information spaces, illustrated by several contemporary systems including Usenet News and CoWebs. Beginning with a general outline of those systems and a history of Usenet News, it looks at the problems of exploring virtual communities and distributed information systems, and of finding information in electronic environments. It outlines the successes and failures of traditional approaches like information filtering, collaborative filtering and information retrieval, and assesses new approaches such as visualisations of social processes and social navigation. Among the key questions covered are: - What aspects of an online group are important to its participants? - How can the specific characteristics of a social information space be used to improve the design of the interface? From Usenet to CoWebs will be essential reading for practitioners working on information spaces, conferencing systems, virtual communities and innovative interfaces to information spaces. It will also provide useful background reading for anyone studying or researching in these areas.