Magento Certified Developer GuideCategory: 1. BasicsDescribe Magento codepools
Manish Prakash Staff asked 5 years ago

Magento has three code pools. Code pools are folder inside the folder ‘app/code’ which contain all magento modules
‘core’: These are all magento core modules. These are prebuild module by magento developers which contain the heart of the system
‘community’: This folder mostly contain all 3rd party magento modules which you install from magento connect other other process.
‘local’: This folder contains any module which you have created yourself

The place where the 3 code pools are included in “app/Mage.php”

    $paths = array();
    $paths[] = BP . DS . 'app' . DS . 'code' . DS . 'local';
    $paths[] = BP . DS . 'app' . DS . 'code' . DS . 'community';
    $paths[] = BP . DS . 'app' . DS . 'code' . DS . 'core';
    $paths[] = BP . DS . 'lib';

    $appPath = implode(PS, $paths);
    set_include_path($appPath . PS . Mage::registry('original_include_path'));

This also shows the priority of 3 code pools.
local > community > core