Great visualizations provide more than a pretty picture and animations; they allow the user to interact with the data, giving them the ability to play with the data to discover the meaning in the data that may not be obvious through a given static presentation.

Exceptional interactions allow the users to steer their way through large amounts of information. It allows them to pan through data too large for a single display, to dive into summary information, and also zoom out to get a higher level view—in essence, it allows users to see the forest from the trees.

Also of great value is the capability to allow the user to easily select, reorder, and reposition visual elements. Through these actions, the user is able to see details of a datum simply by mouseover or touch, to rearrange items for exposing other insights, and to also see how data moves around when reordered. This provides the user a sense of constancy and shows how the data changes when asked...