What is sequence diagram

What is sequence diagrams in UML?

When do we draw sequence diagrams?

UML Sequence Diagrams are interaction diagrams that detail how operations are carried out. They capture the interaction between objects in the context of a collaboration. Sequence Diagrams are time focus and they show the order of the interaction visually by using the vertical axis of the diagram to represent time what messages are sent and when.

Sequence Diagrams captures:

• the interaction that takes place in a collaboration that either realizes a use case or an operation (instance diagrams or generic diagrams)
• high-level interactions between user of the system and the system, between the system and other systems, or between subsystems (sometimes known as system sequence diagrams)

When do you draw sequence diagrams?

You draw sequence diagrams when:

• Model high-level interaction between active objects in a system
• Model the interaction between object instances within a collaboration that realizes a use case
• Model the interaction between objects within a collaboration that realizes an operation
• Either model generic interactions (showing all possible paths through the interaction) or specific instances of a interaction (showing just one path through the interaction)

Free sequence diagram books

Listed below is a rich collection of free UML eBooks related to UML sequence diagrams. If you want to learn more about sequence diagrams or UML, we recommend you to have a look.

More UML books and UML tools

Want to learn more about UML? We have a rich collection of UML books, UML lectures and UML presentations. Check for more details.

If you want to draw UML diagrams, we recommend you try out the UML tools below:

• Visual Paradigm (Desktop) – Award-winning UML modeling software
• Visual Paradigm Online – Easy-to-use UML diagram tool

Enjoy! 🙂