AWS Certification Practice Exam 2026 - Free Amazon Web Services Practice Questions and Study Guide

Elastic Container Registry (ECR) is a fully managed Docker container registry that allows developers to store, manage, and deploy Docker container images. Among its various components, a repository policy defines permissions for users and accounts to access images, an authorization token is required for authentication before pushing or pulling images, and images themselves are the core content stored within ECR.

Docker Compose, however, is not a component of ECR. Instead, it is a tool used for defining and managing multi-container Docker applications, allowing developers to specify the services, networks, and volumes that are required for an application in a simple YAML file. This distinguishes it from ECR, which focuses specifically on the storage and management of container images rather than orchestrating and running multi-container applications.

Understanding this context helps clarify how each component fits within the broader Docker ecosystem and Amazon's suite of services, focusing on the specific role of ECR in container management.