Serverless web application architecture using AWS S3, Cognito, API Gateway, Lambda, and DynamoDB delivers a fully managed, scalable solution without server provisioning. Static assets are hosted on S3, user authentication flows through Cognito User Pool, API requests route via API Gateway to Lambda functions, and data persists in DynamoDB. This pattern eliminates infrastructure management, scales automatically with demand, and reduces operational overhead—ideal for startups and enterprises seeking cost-efficient, event-driven applications. Fork this diagram on Diagrams.so to customize authentication flows, add additional Lambda microservices, or integrate CloudFront for global content delivery. Consider adding API Gateway caching and DynamoDB auto-scaling policies for production workloads handling variable traffic.