Lambda data events record runtime activity of your Lambda functions. With Lambda data events, you can get details on Lambda function runtime. Examples of Lambda function runtime include which IAM user or service made the Invoke API call, when the call was made, and which function was applied. All Lambda data events are delivered to an S3 bucket and CloudWatch Events. You can turn on logging for Lambda data events using the CLI or CloudTrail console and select which Lambda functions get logged by creating a new trail or editing an existing trail.