Which AWS service allows you to deploy serverless applications?

AWS Lambda is a serverless compute service that lets you run code in response to events without provisioning or managing servers. You upload your function code, specify a trigger (such as an API Gateway request, an S3 upload, or a scheduled event), and Lambda automatically scales the execution environment to match the incoming request rate. Because you pay only for the compute time your code actually uses (measured in 100‑millisecond increments) and you don't have to manage the underlying infrastructure, Lambda is the go‑to service for building lightweight, event‑driven applications. It integrates tightly with other AWS services, supports multiple runtimes (Node.js, Python, Java, Go, .NET, etc.), and can be combined with services like API Gateway, Step Functions, and DynamoDB to create fully serverless architectures. For example, a simple REST API that retrieves data from DynamoDB can be implemented entirely with Lambda and API Gateway, requiring no EC2 instances or load balancers. This model reduces operational overhead, improves scalability, and often lowers costs for workloads with variable or unpredictable traffic patterns.