1. Sequence Diagram

2. What is Sequence Diagram?  Sequence Diagram is a dynamic model of a use case, showing the interaction among classes during a specified time period.  Sequence Diagram is used primarily to show the interactions between objects in the sequential order that those interactions occur.

3. Elements of Sequence Diagram  Classes A class is identified by a rectangle with the name inside.  Lifeline A lifeline is identified by a Vertical dashed line. The lifeline represents the time during which the object above it is able to interact with the other objects in the use case.  Activation Bar Activation bar is identified by a narrow vertical rectangle that covers the lifeline. It indicates when an object sends or receives a message

4. Elements of Sequence Diagram  Symbol Class Lifeline Activation

5. Elements of Sequence Diagram  Message: Synchronous message – the caller has to wait for the receiving object to complete execution of the called operation before it can resume execution.  Symbol: Asynchronous message – The caller can execute immediately after sending the message, it does not has to wait for the recipient to handle the message.  Symbol: