The Default Sub-Category Layout box is used to define the page layout for the sub-category page. By default, the box is set to “List”. In List mode sub-categories are displayed in a vertical orientation (i.e. down the page). In Grid mode sub-categories are displayed in a horizontal orientation (i.e. across the page). Each Grid option lists the number of sub-categories that will be displayed across the page. For example, Grid (3) means that three sub-categories will be displayed across and then another three would be displayed below it and so on.