Term Kind Topic What it is
Abstraction Level Discipline practice C4 Model Keeping each diagram to a single level of zoom, and providing separate diagrams for each level rather than one diagram attempting all of them.
C4 Model in Practice practice C4 Model Four nested levels of diagram — context, container, component, code — whose value is controlling altitude rather than the notation itself.
Diagram Maintenance Economics Which Diagrams to Keep, Stale Diagram Cost concept C4 Model The rule that a diagram earns its maintenance cost only when it explains something hard to derive from source - which is why structure diagrams below the container level should be generated or absent.