What Is a Sequence Diagram?

This section describes the UML Sequence Diagram, which presents interaction behaviors of multiple objects by showing communication message interchange sequences between them.

What Is a Sequence Diagram? A Sequence Diagram is a diagram that describes interaction behaviors of multiple objects by showing communication message interchange sequences between them.

In the OMG UML 2.4.1 specification, Sequence Diagram is referred as: Sequence Diagram focuses on the Message interchange between a number of Lifelines.

The picture below shows you a good example of a Sequence Diagram describing interaction behaviors between an email client computer and a server computer with sequenced messages:
UML Diagram Example - Sequence Diagram

Last update: 2014.

Table of Contents

 About This UML Tutorial Book

 Introduction of UML (Unified Model Language)

 UML Class Diagram and Notations

 UML Activity Diagram and Notations

UML Sequence Diagram and Notations

What Is a Sequence Diagram?

 Sequence Diagram - Lifeline Notation

 Sequence Diagram - Message Notation

 Sequence Diagram - Execution Specification Notation

 Sequence Diagram - Frame Notation

 UML State Machine Diagram and Notations

 UML Use Case Diagram and Notations

 MS Visio 2010 - UML Drawing Tool

 References

 PDF Printing Version