This is one example of data visualization using a collapsible tree view. using North Carolina place information. This graphing tool can be used for any type of hierarchical data, for example, an organizational chart. The North Carolina counties, cities, towns, townships, villages, and census-designated places, and unincorporated communities displayed in this graph were extracted from Wikipedia, using the ncplaces Python script, available on github here. The data for the places is visualized using the fantastic d3 library, developed by Mike Bostock.