Video narration
Think of a container as a packaged app. AWS ECS runs these containers for you on AWS. First, you write a task definition: what to run, which image, CPU, memory, and ports. Next, ECS uses a cluster, a pool of compute, to place those tasks onto available resources. If you want the app to stay up, you create a service: it keeps the right number of tasks running, replaces failed ones, and can scale out by launching more containers as demand grows.