What is the difference between a Docker image and a container

Question

I have an image for my PostgreSQL instance and an image for my web application, changes to which keep on being persisted.

What is a container and what is the difference between docker image and container?

Can anyone explain it to me?

Thanks.

Answer 1

Here is very basic explanation for image and container.

 An instance of an image is called a container. You have an image, which is a set of layers as you describe. If you start this image, you have a running container of this image. You can have many running containers of the same image.

You can see all your images with docker images whereas you can see your running containers with docker ps (and you can see all containers with docker ps -a).

So a running instance of an image is a container.

I hope the above explanation will be helpful for you.

Answer 2

Docker Images:  

                     *  Read only templates used to create containers.build by you or other docker users. stored in the docker hub or  your local registry

Docker container:

                   * isolated application platform .containers need to run your application based on images

Answer 3

Images are read-only templates that contain a runtime environment that includes application libraries and applications. Images are used to create containers.

Containers are running instance of image . They are segregated user-space environments for running applications isolated from other applications sharing the same host OS.