<type name="Magento\MediaContentSynchronizationApi\Model\GetEntitiesInterface">
    <arguments>
        <argument name="entities" xsi:type="array">
            <item name="cms_block" xsi:type="string">
                Magento\Cms\Api\Data\BlockInterface
            </item>
            <item name="cms_page" xsi:type="string">
                Magento\Cms\Api\Data\PageInterface
            </item>
        </argument>
    </arguments>
</type>

This is a type configuration.

This configuration is for the base area. Base area configurations will apply to all the sub-applications.

This configuration tells the Object Manager that when a user wants a Magento\MediaContentSynchronizationApi\Model\GetEntitiesInterface object that the following arguments should be used in the foo object's constructor.

• $entities = [...items...];

<preference for="Magento\MediaContentSynchronizationApi\Model\GetEntitiesInterface"
            type="Magento\MediaContentSynchronizationApi\Model\GetEntities"></preference>

This is a preference configuration.

This configuration is for the base area. Base area configurations will apply to all the sub-applications.

This preference configuration tells the Object Manager when a user wants a Magento\MediaContentSynchronizationApi\Model\GetEntitiesInterface object that it should return a Magento\MediaContentSynchronizationApi\Model\GetEntities object.

<type name="Magento\MediaContentSynchronizationApi\Model\GetEntitiesInterface">
    <arguments>
        <argument name="entities" xsi:type="array">
            <item name="catalog_product" xsi:type="string">
                Magento\Catalog\Api\Data\ProductInterface
            </item>
            <item name="catalog_category" xsi:type="string">
                Magento\Catalog\Api\Data\CategoryInterface
            </item>
        </argument>
    </arguments>
</type>

This is a type configuration.

This configuration is for the base area. Base area configurations will apply to all the sub-applications.

This configuration tells the Object Manager that when a user wants a Magento\MediaContentSynchronizationApi\Model\GetEntitiesInterface object that the following arguments should be used in the foo object's constructor.

• $entities = [...items...];