1. Some parts need to scale only when the font size changes. Examples are labels, push buttons, radio button sets, and toggle buttons. These parts need to scale horizontally and vertically so that all of the text for a particular font and size will display correctly. These parts typically do not need to scale proportionally with the entire window (although they can).

2. Other parts, including entry fields and drop-down lists, need to scale with font size and can also scale horizontally with the entire window so that they display as much text as possible.

3. Finally, parts such as lists, multiline edit views, notebooks, and containers can scale both horizontally and vertically as the window size changes, so as much text or as many items as possible are displayed.