Days are gone when you have to keep some server running for your cloud computation needs, this works good when you have millions of request daily and you your server capable of handling those request.
Now you can deploy your application as independent functions on AWS lamda service which will responds to events. The benefit of server-less architecture is that you pay only when your function get called and it will auto scale.
Lamda functions responds to events from all AWS services and you can also create your own API using AWS API Gateway to respond to your application events.
Lambda runs your code on high-availability compute infrastructure and performs all the administration of the compute resources, including server and operating system maintenance, capacity provisioning and automatic scaling, code and security patch deployment, and code monitoring and logging. All you need to do is supply the code.
To know more about lamda visit: https://aws.amazon.com/lambda/details/