These modifications allow you to assign specific products and categories to multiple stores that you define in the administration panel. The products and categories
will not be able to be manipulated via the web-browsers address bar (like in most
other multi-shop implementations). Also, there is no "one store to rule them all".
You decide which categories you want displayed on which store-front. You decide
which products in that category you want displayed on which store-front. Shopping
carts are NOT shared between the sites.