Good visualizations use graphics to organize information, highlight important information, allow for visual comparisons, and reveal patterns, trends, and outliers in the data. Some principles include:

• Preattentiveness
• Visual components that are useful for making quantitative comparisons. Graphical vocabulary consisting of marks (points, lines, areas), retinal variables (color, size, shape, orientation, scale), and position (relative locations of marks within a spatial field).
• Gestalt principles (proximity)