AWS provides various logging and monitoring web services that enable you to log, monitor and record the activities in your AWS account.
CloudTrail is an AWS web service that enables you to log, continuously monitor, and retain account activity related to actions across an AWS infrastructure.
CloudTrail logs events taken in the AWS Management Console, AWS Command Line Interface, and AWS SDKs and APIs.
Amazon CloudWatch monitors AWS resources and the applications running on AWS and on-premises servers in real-time. CloudWatch collects data in the form of logs, metrics, and events.
References: AWS CloudTrail