Getting started with Docker: images, containers and commands

Docker packages an application and everything it needs into a "container" that runs the same anywhere. Here are the core concepts and first commands.

Image vs container

An image is a template (for example "nginx"). A container is a running instance of that image. From one image you can start any number of containers.

1. Run your first container

docker run -d -p 8080:80 --name web nginx

Downloads the nginx image and starts a container, mapping the server's port 8080 to the container's port 80.

2. Basic commands

docker ps                # running containers
docker ps -a             # all containers
docker stop web          # stop
docker start web         # start
docker rm web            # remove
docker images            # downloaded images

3. Enter a container

docker exec -it web bash

Next steps

If you do not have Docker installed, pick Docker from the one-click app catalog. Then move on to Docker Compose for multi-service apps.