Rewriting history: more power to creative people

Trying out different alternatives is a natural part of creative work, resulting in several versions that are hard to manage. With the tools available today, we often end up having to manually redo changes that worked in one version on other versions. We propose a new approach for supporting creative work: an artifact is described as the history of the operations that created it. We show that by allowing users to change this history, the common use cases of merging, generalizing and specializing can be supported efficiently. This rewriting history approach is based on a formal specification of the operations offered by a tool, leads to a new theory of operations, and enables exciting new ways to share and combine creative work. It is complementary to state-based version control, and offers the user a new understanding of merging. The approach was implemented for a collaborative drawing tool, and evaluated in a user study. The study shows that users understand the approach and would like to use it in their own creative work.