ECS Task in AWS is an AWS tool for running and managing containerized applications. It enables developers to deploy and scale applications quickly, easily, and securely on a managed cluster of virtual machines. With ECS Task, customers can specify which compute resources to use in the form of Amazon EC2 instances or AWS Fargate. They can also define how their containers should be configured, monitored, and secured while they are running. By using ECS Task's powerful features such as automatic scaling, rolling updates and service discovery, customers can ensure that their applications are running with optimal performance at all times.