For many Web-based applications, it's important to be able to analyze the paths
users have taken through a site--for example, to understand how they're discovering
engaging content. These paths are difficult to summarize visually because of the
underlying data's complexity. A Google researcher applied a sunburst visualization
to this problem, after simplifying the data into a hierarchical format. The
resulting visualization was successful in YouTube and is widely referenced and
accessed. The code for the visualization is available as open source.