What term refers to the empty areas that form the canvas for any pages making use of the layout?

The term that refers to the empty areas forming the canvas for any pages utilizing the layout is "Placeholders." Placeholders serve as defined regions within a layout where content, such as text, images, or other UI components, can be added. They act as flexible zones that can be populated with various elements, enabling developers to create dynamic and customizable interfaces.

In Mendix, placeholders help to structure the user interface effectively, as they delineate where UI components can be inserted, ensuring that layout designs remain organized and visually appealing. This is crucial for maintaining consistency across different pages and enhancing the user experience by allowing for a modular approach to page design. By defining the areas where components will be displayed, developers can manage the layout more efficiently while ensuring that each page's content aligns correctly within the intended design.