C4 Model

1. Abstractions: software system

   The highest level of abstraction in C4.

2. Abstractions: container

   Separately deployable or runnable units.

3. Abstractions: component

   Groupings of related functionality inside a container.

4. System context diagram

   Level 1 diagram showing users and external systems.

5. Container diagram

   Level 2 diagram showing runtime containers.

6. Component diagram

   Level 3 diagram of components.

7. Dynamic diagram

   Collaboration flows between elements.

8. Deployment diagram

   Mapping software to infrastructure.

9. Diagram notation

   Notation guidance for titles, colors, and legends.

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