use docker image

Docker images are an integral part of containerized applications. This straightforward article guides you through how to use Docker images effectively.

Understanding Docker Images

A Docker image is a lightweight standalone executable package, which includes all the software required to run an application — the code, runtime, libraries, environment variables, and config files. They provide a means of packaging software so that it always runs the same, irrespective of its environment.

Step 1: Installing Docker

To get started with Docker images, you first need to install Docker. Visit the official Docker website and download the correct installation file suitable for your operating system. After downloading, install it, and then check it’s properly installed by typing docker --version in your terminal.

Step 2: Pulling Docker Images

To use Docker images, you need to retrieve them from a Docker registry. The Docker Hub is the default public repository where you can find a vast number of Docker images. To pull an image, simply use the command docker pull [image_name]. For instance, pulling the hello-world image can be accomplished by typing docker pull hello-world into the terminal.

Step 3: Running Docker Images

After pulling an image, you can run it using the docker run command followed by the image name, like this: docker run hello-world. Once you run this command, Docker will start a container using the hello-world image.

Step 4: Listing Docker Images

To see all the Docker images available on your system, you can use the docker images command. This command returns a list of your local Docker images, their repository, tag, image ID, and the size.

Step 5: Removing Docker Images

If you want to remove an unused image from your system, you can use the docker rmi or docker image rm commands followed by either the image ID or image name. Be careful as this will permanently remove the image from your system.

Docker images are the cornerstone of Docker. By mastering Docker images, you are on your way to proficiently utilizing the powerful features of Docker, leading to improved software deployment processes.