<type name="Magento\Customer\Ui\Component\DataProvider">
    <arguments>
        <argument name="reporting" xsi:type="object">
            CustomerGridCollectionReporting
        </argument>
    </arguments>
</type>

This is a type configuration.

This configuration is for the adminhtml area. This is the area that corresponds with the Magento admin sub-application.

This configuration tells the Object Manager that when a user wants a Magento\Customer\Ui\Component\DataProvider object that the following arguments should be used in the foo object's constructor.

• $reporting = new CustomerGridCollectionReporting (...)

<virtualType name="CustomerGridCollectionReporting"
             type="Magento\Framework\View\Element\UiComponent\DataProvider\Reporting">
    <arguments>
        <argument name="filterPool" xsi:type="object">
            CustomerGirdFilterPool
        </argument>
    </arguments>
</virtualType>

This is a virtual type configuration.

This configuration is for the adminhtml area. This is the area that corresponds with the Magento admin sub-application.

This virtualType configuration tells the Object Manager when a user wants a virtual CustomerGridCollectionReporting object that it should return a Magento\Framework\View\Element\UiComponent\DataProvider\Reporting object.

This configuration tells the Object Manager that when a user wants a CustomerGridCollectionReporting object that the following arguments should be used in the foo object's constructor.

• $filterPool = new CustomerGirdFilterPool (...)