What are the basic extend and implement classes for Magento2?

magento

Model: extends \Magento\Framework\Model\AbstractModel ResourceModel: extends \Magento\Framework\Model\ResourceModel\Db\AbstractDb Collection: extends \Magento\Framework\Model\ResourceModel\Db\Collection\AbstractCollection Block : extends \Magento\Framework\View\Element\AbstractBlock Helper : extends \Magento\Framework\App\Helper\AbstractHelper InstallData: implements InstallDataInterface InstallSchema: implements InstallSchemaInterface UpgradeData: implements UpgradeDataInterface UpgradeSchema: implements UpgradeSchemaInterface