A Docker image is a read-only template containing a set of instructions for creating a container that can run on the Docker platform. It provides a convenient way to package up applications and preconfigured server environments, which can be used for private use or shared publicly with other Docker users
. An image is composed of multiple stacked layers, like layers in a photo editor, each changing something in the environment. It contains the code or binary, runtimes, dependencies, and other filesystem objects to run an application
. When you use Docker, you are creating and using images, containers, networks, volumes, plugins, and other objects
