What is a collection?

The word 'collection' has been common currency in what we accept as the real world of objects and events, and has been imported with seemingly little effort into our discourse about the digital world, yet there is no clear definition in either domain of what is meant by the term. We clarify this issue by first examining how the term is used in the contemporary information science literature and then by going on to establish the criteria which are employed in bringing a collection about. We will argue that the assumption that there is a realist permanence or fixity in the world that determines taxonomies is false, and that the only feasible approach to the construction of categories to which objects, whether digital or physical, are allocated is an anti-realist one where attention is paid to the intentions and subsequent decisions of the collector