Now that all three tiers of your application are available in containers, you'll need to push those images to container registries. Registries are the container equivalent to repositories for your code. Registries can be public or private.
In this lesson, we'll use Docker Hub to push our images. Docker Hub repositories allow you share container images with your team, customers, or the Docker community at large.
Docker images are pushed to Docker Hub through the
[docker push](https://docs.docker.com/engine/reference/commandline/push/) command. A single Docker Hub repository can hold many Docker images (stored as tags).
Images pushed to a public registry can be downloaded by using the
docker pull command. Once they have the image downloaded, they can use Docker run to start each container just like you did in the previous steps.