1. A method comprising: enabling a job to be done using pieces of knowledge that relate to a domain of human activity and that are stored in respective places each under the control of a system that can perform one or more defined tasks with respect to the piece stored there, the enabling comprising defining conceptual nodes, each node identifying at least one of the pieces of knowledge and at least one of the tasks that can be performed using the piece of knowledge, the pieces and the tasks being defined using subsets of a common vocabulary associated with the domain of human activity, and expressing the job to be done in the common vocabulary and without specifying the location of the pieces of knowledge needed to perform the job or the tasks to be performed to complete the job, and enabling the job to be done by causing one or more of the conceptual nodes to perform one or more of the tasks on one or more of the pieces of information, without requiring storage of copies of the pieces of knowledge anywhere other than the places that are under control of the systems.