AWS Lambda is a zero-administration compute platform for back-end web developers that runs your code for you in the AWS cloud and provides you with a fine-grained pricing structure. AWS Lambda runs your back-end code on its own AWS compute fleet of Amazon Elastic Compute Cloud (Amazon EC2) instances across multiple Availability Zones in a region, which provides the high availability, security, performance, and scalability of the AWS infrastructure.

Developer Guide
Provides a conceptual overview of AWS Lambda, includes detailed instructions for using the various features, and provides a complete API reference for developers.