.. include:: global.rst

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Containers
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.. note::

   **Main Components of Docker (in order):**

   - **Dockerfile**
     - A recipe that tells Docker how to build an image (OS or application).

   - **Docker Image**
     - Built from a Dockerfile.
     - Can be distributed via a Docker image repository.

   - **Docker Container**
     - Created from an image.
     - Runs the software that executes code and commands.
     - Has two states: *Stopped* and *Running*.
     - Modes of operation:
      - As a server that awaits requests.
      - Short life.
      - Long life.

   **Final takeaway:**  
   A Dockerfile defines how to build an image → an image becomes a container → the container runs the application.