M2 Common provides utility elements available in every project alongside whatever M2 metamodels are in use. These are not specific to any notation — they supplement all metamodels.
| Type | Shape | Colour | Description |
|---|
| Note | note (folded corner) | #FFF9C4 (yellow) | A comment or annotation placed on a diagram. Connect to elements with an Annotation relationship. |
| Text | text (no border) | transparent | A free-form text label on the diagram canvas. For titles, section headings, or any label that doesn’t need to be a formal model element. |
| Boundary | boundary (dashed border) | transparent | A visual grouping region that organises related elements on a diagram. No semantic meaning — purely visual. |
| Artifact | rectangle | #F5F5F5 (light grey) | A reference to an external document, file, or deliverable. Bridges the gap between the model and supporting documentation. |
| Type | Line Style | Markers | Colour | Constrained | Description |
|---|
| Trace | dashed | arrow at target | #16a34a (green) | No | Traceability link showing that one element is derived from or corresponds to another. No dependency implied. |
| Realization | dotted | hollow arrow at target | #16a34a (green) | No | One element realizes or implements another. Source is concrete; target is abstract. |
| Annotation | dotted | none | #16a34a (green) | Yes — source must be a Note | Connects a Note to the element it annotates. Purely visual — carries no semantic meaning. |
| Dependency | dotted | arrow at target | #16a34a (green) | No | One element requires or depends on another to function correctly. Implies a runtime or structural need. |
- M2 Common is always present and read-only in every project
- Common types appear in the Palette alongside the active M2 metamodel’s types
- Common types are available on all diagrams regardless of which M2 metamodel the diagram uses
- All four relationship types use a green colour (#16a34a) to visually distinguish them from notation-specific relationships