<type name="Magento\Vault\Model\PaymentTokenFactory">
    <arguments>
        <argument name="tokenTypes" xsi:type="array">
            <item name="account" xsi:type="const">
                Magento\Vault\Api\Data\PaymentTokenFactoryInterface::TOKEN_TYPE_ACCOUNT
            </item>
            <item name="credit_card" xsi:type="const">
                Magento\Vault\Api\Data\PaymentTokenFactoryInterface::TOKEN_TYPE_CREDIT_CARD
            </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\Vault\Model\PaymentTokenFactory object that the following arguments should be used in the foo object's constructor.

• $tokenTypes = [...items...];

<preference for="Magento\Vault\Api\Data\PaymentTokenFactoryInterface"
            type="Magento\Vault\Model\PaymentTokenFactory"></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\Vault\Api\Data\PaymentTokenFactoryInterface object that it should return a Magento\Vault\Model\PaymentTokenFactory object.