Template style is a feature introduced in Joomla! 1.6.x that allows users to assign different template styles to individual menu items. By default, Joomla! assigns a template style to all menu items upon installation. A yellow star indicates the default template style in use. A default template style can be partially or completely overridden by assigning different template styles to the desired menu items in order to obtain a different look for their respective pages.
A template style can be assigned to menu items either under Extensions > Template Manager or by editing a menu item under Menus > Menu Name > Menu item.