<virtualType name="AmazonLogger"
             type="Magento\Payment\Model\Method\Logger">
    <arguments>
        <argument name="config" xsi:type="object">
            AmazonGatewayConfig
        </argument>
    </arguments>
</virtualType>

This is a virtual type configuration.

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

This virtualType configuration tells the Object Manager when a user wants a virtual AmazonLogger object that it should return a Magento\Payment\Model\Method\Logger object.

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

• $config = new AmazonGatewayConfig (...)