Metadata about the snapshot, including when it was extracted, the tenant ID, and the name of the sending system. Conceptual variables included in the snapshot. Represented variables included in the snapshot. Instance variables included in the snapshot. Populations included in the snapshot. Universes included in the snapshot. Unit types included in the snapshot. Datasets included in the snapshot. Dataset collections included in the snapshot. Organizations included in the snapshot. Statistical classifications included in the snapshot. Code lists included in the snapshot. Categories included in the snapshot.