AWS Serverless Application Model (SAM) is an open-source serverless development tool that simplifies the process of building and running serverless applications on AWS. SAM transform uses a shorthand syntax to generate infrastructure as code, while SAM CLI provides developer workflows like build, package, and test using CloudFormation. The tool supports all Lambda runtimes and offers pre-built application templates for common use cases. Developers can test applications locally or use SAM Accelerate for cloud testing, shortening the troubleshooting cycle. SAM Pipelines integrate with popular CI/CD tools for production-ready deployments, and the tool is compatible with many authoring, development, and deployment services.