AWS Lambda and Serverless

AWS Lambda lets you run code without provisioning or managing servers. You pay only for the compute time you consume — there is no charge when your code is not running. Lambda is the cornerstone of serverless computing on AWS.

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What Is Serverless?

Serverless doesn't mean there are no servers — it means you don't manage them. The cloud provider handles all the infrastructure: provisioning, scaling, patching, and availability.

Serverless Benefits

• No server management — focus entirely on your code
• Automatic scaling — from zero to thousands of concurrent executions
• Pay-per-use — charged only for actual compute time
• Built-in high availability — runs across multiple AZs automatically

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How Lambda Works

The Execution Model

1. You upload your code (a "function")
2. You configure a trigger (what causes the function to run)
3. When the trigger fires, Lambda runs your code in a managed environment
4. Lambda scales automatically — each trigger invocation gets its own execution environment

Supported Runtimes