I'm studying UML and I am confused.Could anyone explain me What is the difference between use-case diagram and sequence diagram in unified process model?
The use-case diagram shows the objectives that make external actors interact with the system. It‘s about relations with the outside world. Each use-case is independent and not sequenced with the others.
The sequence diagram shows a scenario of interaction between objects within the system. The interaction in the diagram correspond to message that are exchanged in a given sequence.