A container registry is a central repository for container images. Popular public container registries include Amazon Elastic Container Registry (ECR), Azure Container Registry, Docker Hub, Google Container Registry, and Quay.io (Red Hat).
Container registries are a foundational component of a modern cloud-native deployment pipeline. Typically, container images are built by a continuous integration system which pushes (uplaods) the image to the container registry. A Kubernetes cluster then downloads the container image from the registry.