1. System Level Logical Level Visual Level The System level

2. LightBulb System Level Logical Level Visual Level

3. LightBulb + Context System Level Logical Level Visual Level

4. 2 LightBulbs, 1 Box: modeling the system System Level Logical Level Visual Level

5. Adding command sending System Level Logical Level Visual Level

6. Adding feedback System Level Logical Level Visual Level

7. The Logical Level System Level Logical Level Visual Level

8. Logical LightBulb System Level Logical Level Visual Level

9. Logical LightBulb + Context System Level Logical Level Visual Level

10. System+Logical Levels: interaction System Level Logical Level Visual Level +

11. The Visual Level System Level Logical Level Visual Level

12. Visual widgets models System Level Logical Level Visual Level

13. Visual widgets + contexts System Level Logical Level Visual Level

14. Visual control for 1 Lightbulb System Level Logical Level Visual Level

15. 3 Levels interacting System Level Logical Level Visual Level + +