A histogram is used to visualize the number of cells with certain levels of volume. 

Expected result: Two cell types sort and produce an approximately normal distribution of cell volumes.

If you do not see both a cell field and a histogram panel, use the Window menu of CC3D Player to restore these windows.

Relevant documentation: https://compucell3dreferencemanual.readthedocs.io/en/latest/example_plots_histograms.html#histograms