| Configuration (CO) |
atomic positions/types, lattice vectors, PBCs |
| Property Instance (PI) |
computed property (energies, forces, stress, …) along with specific computational settings when available |
| Property Definition (PD) |
explicit, computer-readable definition of the contents of a property |
| Data Object (DO) |
grouping of a single CO with one or more PI |
| Configuration Set (CS) |
a grouping over configurations to improve organization and interpretability |
| Dataset (DS) |
the complete dataset as a union of CSs and DOs for publishing/exploring |
| Metadata (MD) |
extra, user-specified, key-value paired information |
