"Several AWS services, such as Amazon Simple Storage Service and Amazon Simple Notification Service, invoke functions asynchronously to process events. When you invoke a function asynchronously, you don't wait for a response from the function code. You hand off the event to Lambda and Lambda handles the rest. You can configure how Lambda handles errors, and send invocation records to a downstream resource to chain together components of your application."
"AWS Lambda now supports Destinations for asynchronous invocations, a new feature that allows you to gain visibility to asynchronous invocation result and route the result to an AWS service without writing code"