Architecting and designing : UML 2.0 Lite : UML models : UML class diagrams : Visibility
  
Visibility
Each attribute or method displayed on a class symbol in UML is prefaced by a visibility adornment, which you specify in the definition dialog of the respective attribute or method. The following adornments specify visibility:
+ public visibility
# protected visibility
- private visibility
See also
UML class diagrams