Docker best practices

My succint summary of the Docker best practices according to the link below.

https://docs.docker.com/develop/develop-images/dockerfile_best-practices/#Each container should have only one concern

• Containers should be ephemeral - it can be terminated and a new one launched with a minimum effort to set-up and configuration
• Use multi-stage builds to reduce image size
• Avoid installing unnecessary packages
• Each container should have only one concern
• Minimize the number of layers