IBM History Flow tool

IBM's History Flow tool is a visualization tool for a time-sequence of snapshots of a document in various stages of its creation. The tool supports tracking contributions to the article by different users, and can identify which parts of a document have remained unchanged over the course of many full-document revisions. The tool was developed by Fernanda Viégas, Martin Wattenberg, Jonathan Feinberg, and Kushal Dave of IBM's Collaborative User Experience research group.

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