This paper discusses some fundamental aspects of digitally produced, process-based visual and aural art. Specifically these are its basis in the physical world; its representation using formal abstract notation; and finally its re-emergence into the physical world as an event or artefact to be experienced by a human observer. Notations for representing temporal and spatial events are discussed in light of their contribution to process-based art making. Parallels are drawn between the specification of musical notes and the specification of locations in physical space using abstract sets of symbols. It is shown how the development of notation paved the way for the digital synthesis of artefacts and events. Finally, this paper speculates on a future direction for process-based art–the development of computer-controlled form–and shows that conceptually it is an extrapolation from existing computational techniques for event and artefact synthesis.