Config files

Module configuration files are found in the etc folder under a module's main directory.


You can override the settings of any module in any other module simply by putting in the correct XML tags. This is 
the essence of overriding in Magento.

You can create any class for any purpose, and to install it into the system you create a new config.xml that 
specifies your class name in the same spot where the original class was defined. This is also why you will see 
method calls like getModel('catalog/product') used throughout the system instead of a more simple approach like  
new Catalog_Model_Product().