At the heart of any discussion of the information sciences, at least when this discussion is held in the English language, lies the problem of the variant, and shifting, set of concepts and meanings of the terms 'library' and 'information'. The term 'information', in particular, has a variety of meanings in different contexts and communities of discourse, providing an excellent example of Wittgenstein's 'language game'. This implies that any terminology built around this central concept is in danger of being constructed on 'shifting sands'. This article outlines, for the English language only, some of these diverse meanings of information, and their consequences for the terminology of the information sciences. It focuses on the variant relationships between information and related concepts, particularly data and knowledge. It also includes an account of the view of information taken in the hard and soft methodologies of systems science, as well as the new discipline of 'information physics'. From this, some remarks may be made on the changing meanings of complex terms such as 'information technology' and 'information literacy: as well as those complex terms involving 'management', information management, knowledge management, document management etc. A similar, though shorter, treatment will be given to terminology around the 'library' concept, particularly in view of the change toward viewing a library as an organised virtual information space, rather than a physical environment.
