The box model comprises the set of properties that define parts of an element that take up space on a web page. The model includes the content area’s size (width and height) and the element’s padding, border, and margin. The properties include:

1. width and height: The width and height of the content area.
2. padding: The amount of space between the content area and the border.
3. border: The thickness and style of the border surrounding the content area and padding.
4. margin: The amount of space between the border and the outside edge of the element.