DockerHub which is like Github but for servers. You can host your own also • Image - Readonly templates that contain your operating system and files. Images are stored in registries • Container - This is your virtualized operating system. Uses namespaces, control groups, and union file systems. Containers are built from templates called images. I can also save the container state to be used as a template for another container • Dockerfile - A Makefile for your image. Contains the steps needed to produce the container. So what does run mean.