This document discusses serverless architectural patterns and best practices using AWS services like AWS Lambda, Amazon API Gateway, Amazon S3, Amazon DynamoDB, and Amazon Kinesis. It covers four common patterns: 1) 3-tier web applications, 2) batch processing, 3) stream processing, and 4) automation. For each pattern, it discusses considerations, example architectures, and best practices. It provides guidance on designing resilient and scalable serverless applications and systems.