The pack geometry manager acts based on the concept of using up free space within the parent widget. When packing, you can specify at which end of the free space to put the widget, and how it will grow along with said free space (as the window itself grows and shrinks). The geometry manager than assigns widgets into said free space, leaving as little empty space as possible.
The pack geometry manager is primarily controlled by three keyword arguments:
- side: On which end of the available space do you want to place the widget? The options are defined as constants within Tkinter, as LEFT, RIGHT, TOP, and BOTTOM.
- fill: Do you want the widget to fill any available space around it? The options are also constants: X or Y. These are Cartesian, ...