As you learned in Chapter 5, WPF windows are filled with elements, but only some of these elements are controls. Controls are user-interactive elements—elements that can take focus and receive input from the keyboard or mouse.
All controls derive from the System.Windows.Control class, which adds a bit of basic infrastructure:
The ability to set the alignment of content inside the control
The ability to set the tab order
Support for painting a background, foreground, and border
Support for formatting the size and font of text content
You've already learned about the first two points. (Chapter 5 covered content and alignment, while Chapter 6 explored the subtleties of focus and tab order.) The following sections cover brushes and ...