Docker Architecture

1. Docker Client:

a. This is where the user interacts with Docker using commands like docker build, docker run, docker pull, etc. b. It sends these commands to the Docker Daemon. 

 2. Docker Daemon (dockerd):

 a. This is the background service that actually performs all Docker operations like building images, running containers, and communicating with the Docker registry.

 b. It listens to the Docker Client's requests and manages Docker objects.

 3. Dockerfile:

 a. A text file that contains a set of instructions to create a Docker image. 

 b. The Docker Daemon reads this file to build a Docker image using the docker build command. 

 4. Docker Image:

 a. A read-only template that contains the application code, runtime, libraries, and dependencies.

 b. This is built from the Dockerfile and used to launch containers. 

 5. Docker Container: 

 a. A running instance of a Docker image.

 b. It is isolated, lightweight, and portable — runs your application in a self-contained environment. 

 6. Docker Registry:

 a. A place where Docker images are stored.

 b. Common registries include Docker Hub, AWS ECR, GitHub Container Registry, etc.

 c. Images can be pulled from or pushed to the registry by the Docker Daemon.  

� � Flow of the Architecture: 

 1. You write a Dockerfile. 

 2. Use Docker Client to run docker build.

 3. The Docker Daemon reads the Dockerfile and creates a Docker Image.

 4. This image can be: a. Run as a Docker Container, or b. Pushed to a Docker Registry for sharing or future use. 

 5. Later, you can pull the image from the registry and run it again as a container.