AWS Lambda - Introduction to AWS Lambda and serverless computing.

AWS Lambda is a serverless computing service from Amazon Web Services (AWS) that runs code in response to events without needing to manage servers. It scales automatically and you only pay for the compute time you use.

### Key Concepts

1. Event-Driven: Lambda functions are triggered by events from AWS services like S3, DynamoDB, or HTTP requests via API Gateway.

2. Stateless: Each invocation is independent, with Lambda managing the underlying infrastructure.

3. Automatic Scaling: Functions scale automatically with the workload.

4. Pay-per-Use: Charges are based on request count and execution time.

### Benefits

- Reduced Operational Complexity: No server management required.

- Cost Efficiency: Pay only for active compute time.

- Automatic Scaling: Scales with demand automatically.

- Enhanced Productivity: Focus on code rather than infrastructure.

### Use Cases

- Data Processing: Real-time processing, such as image resizing.

- Backend Services: RESTful APIs with API Gateway.

- Automated Tasks: Scheduled reports, backups.

- Event Handling: Responding to events from services like S3.

### Example: Simple Python Lambda Function

python

import json

def lambda_handler(event, context):

print("Received event: " + json.dumps(event, indent=2))

return {

'statusCode': 200,

'body': json.dumps('Hello from Lambda!')

}

This function logs the event data it receives and returns a message. AWS Lambda simplifies building scalable, cost-effective applications by abstracting server management.