Which service can be used for building and integrating loosely-coupled, distributed applications?

Amazon Simple Notification Service (Amazon SNS) is a web service that makes it easy to set up, operate, and send notifications from the cloud. Amazon SNS is used for building and integrating loosely-coupled, distributed applications. NOTE: Sometimes AWS will expand abbreviations in answers and other times, like with this question, you just get the abbreviation. Therefore, there’s no workaround, you have to know your abbreviations!