The Diagram Window in this case is showing the Ancestors and Descendants of Cameron Peabody. Ancestors are shown in the top-half of the window (green boxes), descendants of Cameron Peabody or his siblings and their descendants, are shown with a yellow background. Spouses (relatives by marriage) are shown in brown. Cameron Peabody's own box has a white background. These colours are fully-configurable, as are the background colours of the window itself, the text colour, the font colour, the contents of each box, and most other aspects of the diagram.

In this example the Diagram Window is filling the frame of the application window. However, you can look at both the Diagram Window and the Records Window at the same time - side-by-side, or overlapping - if you wish. You can have as many diagrams open at any time as you like, and you can switch between them, or other windows, by cicking on the appropriate icon on the Navigation Bar. The Navigation Bar is the grey strip on the left side, currently showing one icon for the Diagram Window and another for the Record Window.