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Is an agile method for developing user stories. The task is to begin assume the role of a user for the application and to document the tasks or stories that a user will do while interacting with the application. Stories are then mapped on a board like a time line with the critically of the stories ranked in a vertical axis. The goal of the exercise is to represent stories as a workflow, and end to end set of tasks that a user will likely do when they are interacting with the application. The effort is to identify gaps or areas of functionality that are currently unplanned and to begin to group iterations into the smallest units of functionality that would be of benefit to an end user of the application.
These ideas come from the Open Cast Matterhorn project at UC Berkeley (http://www.opencastproject.org/).
Link to USD documentation on Story Mapping Exercise
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