- In RDFS, you can subclass existing classes…
 - … but, otherwise, that is all you can do
 - In OWL, you can construct classes from existing ones:
						
- enumerate its content
 - through intersection, union, complement
 - through property restrictions
 
 - To do so, OWL introduces its own 
Class… - … and 
Thingto differentiate the individuals from the classes