The Global-Website-Store methodology
Magento has, since the very beginning of version 1, included a very elegant yet powerful means of creating and configuring multiple stores within a single installation. This structure is based on what we call the Global-Website-Store methodology or hierarchy.
Take a look at this diagram:
Global refers to any configuration or setting that affects the entire Magento installation. Some settings such as security, product SKUs, and logging apply to all stores.
Website is akin to a business entity as many of the settings made at this level pertain to payment gateways, shipping, taxes, and so on. Therefore, if you have one business entity, you'll most likely have one Website entity, regardless of how many stores you might create within this business. On the other hand, if you want to create another Website entity that has different business-related settings across other stores, Magento makes this possible. In this hierarchy, Website is not the public site...
