A computerized interactor system uses physical, three-dimensional objects as metaphors for input of user intent to a computer system. When one or more interactors are engaged with a detection field, the detection field reads an identifier associated with the object and communicates the identifier to a computer system. The computer system determines the meaning of the interactor based upon its identifier and upon a semantic context in which the computer system is operating. The interactors can be used to control other systems, such as audio systems, or it can be used as intuitive inputs into a computer system for such purposes as marking events in a temporal flow. The interactors, as a minimum, communicate their identity, but may also be more sophisticated in that they can communicate additional processed or unprocessed data, i.e. they can include their own data processors. The detection field can be one-dimensional or multi-dimensional, and typically has different semantic meanings associated with different parts of the detection field.