Core Components of Docker
Docker Engine is one of the core components of Docker. It is responsible for the overall functioning of the Docker platform.
Docker Engine is a client-server based application and consists of 3 main components.
- Server
- REST API
- Client
The Server runs a daemon known as dockerd (Docker Daemon), which is nothing but a process. It is responsible for creating and managing Docker Images, Containers, Networks and Volumes on the Docker platform.
The REST API specifies how the applications can interact with the Server, and instruct it to get their job done.
The Client is nothing but a command line interface, that allows users to interact with Docker using the commands.
Docker Terminology
Let us take a quick look at some of the terminology associated with Docker.
Docker Images and Docker Containers are the two essential things that you will come across daily while working with Docker.
In simple terms, a Docker Image is a template that contains the application, and all the dependencies required to run that application on Docker.
On the other hand, as stated earlier, a Docker Container is a logical entity. In more precise terms, it is a running instance of the Docker Image.
Docker Editions
Docker is available in 2 different editions, as listed below:
- Community Edition (CE)
- Enterprise Edition (EE)
The Community Edition is suitable for individual developers and small teams. It offers limited functionality, in comparison to the Enterprise Edition.
The Enterprise Edition, on the other hand, is suitable for large teams and for using Docker in production environments.
The Enterprise Edition is further categorized into three different editions, as listed below:
- Basic Edition
- Standard Edition
- Advanced Edition
What is Docker Hub?
Docker Hub is the official online repository where you could find all the Docker Images that are available for us to use.
Docker Hub also allows us to store and distribute our custom images as well if we wish to do so. We could also make them either public or private, based on our requirements.
Please Note: Free users are only allowed to keep one Docker Image as private. If we wish to keep more than one Docker Image as private, we need to subscribe to a paid subscription plan.