| # | Concept | Culture | Statement | Freq. |
|---|---|---|---|---|
| 1 | progressive rock | United Kingdom | Progressive rock, or 'prog rock', emerged in late 1960s United Kingdom with complex compositions and instrumental virtuosity. | 5 |
| 2 | progressive rock | United States | Progressive rock in the United States emphasizes complex musical structures, long instrumental solos, and thoughtful lyrics. | 5 |