Serverless encompasses services, practices, and strategies that
enable organisations to build more agile applications allowing them to innovate and respond to change faster.
With serverless computing, infrastructure management tasks like capacity provisioning and patching are handled by AWS, so project teams could focus only on writing code that serves their customers.
Serverless services like AWS Lambda come with automatic scaling, built-in high availability, and a pay-for-value billing model.
https://aws.amazon.com/serverless/