UML diagrams

What is it?

The Unified Modeling Language (UML) is a general-purpose, developmental, modeling language in the field of software engineering, that is intended to provide a standard way to visualize the design of a system.

UML was originally motivated by the desire to standardize the disparate notational systems and approaches to software design developed by Grady Booch, Ivar Jacobson and James Rumbaugh at Rational Software in 1994–95, with further development led by them through 1996.

There are 14 types of diagrams each one is important to the develoment of software:

  1. Class Diagram

     

  2. Component Diagram

     

  3. Deployment Diagram

     

  4. Object Diagram

     

  5. Package Diagram

     

  6. Profile Diagram

     

  7. Composite Structure Diagram

     

  8. Use Case Diagram

     

  9. Activity Diagram

     

  10. State Machine Diagram

     

  11. Sequence Diagram

     

  12. Communication Diagram

     

  13. Interaction Overview Diagram

     

  14. Timing Diagram

 

Class diagram:

Class diagrams are arguably the most used UML diagram type. It is the main building block of any object oriented solution. It shows the classes in a system, attributes and operations of each class and the relationship between each class.

In most modeling tools, a class has three parts, name at the top, attributes in the middle and operations or methods at the bottom. In large systems with many related classes, classes are grouped together to create class diagrams. Different relationships between classes are shown by different types of arrows.

UML Class Diagram Example

Use case diagram:

As the most known diagram type of the behavioral UML diagrams, Use case diagrams give a graphic overview of the actors involved in a system, different functions needed by those actors and how these different functions are interacted.

It’s a great starting point for any project discussion, because you can easily identify the main actors involved and the main processes of the system.

Use Case Diagram in UML