1. Evolution of UML

2. What is UML UML stands for Unified Modeling Language.
UML is a way of visualizing a software program using a collection of diagrams. The notation has evolved from the work of Grady Booch, James Rumbaugh, Ivar Jacobson, and the Rational Software Corporation in 1997 to be used for object-oriented design, but it has since been extended to cover a wider variety of software engineering projects. Today, UML is accepted by the Object Management Group (OMG) as the standard for modeling software development

3. Different Versions of UML
UML 1.0 and UML 2.0 are two different versions of UML. UML 1.0 is greatly influenced by the OMT notations. However, it suffers from weak semantic integration. UML 2.0 tackles the issues related to the weak semantic integration. However, it also suffers from constraints like overloaded notation, lack of precise semantics and lack of methodological basis like usage types, etc.

4. Different Versions of UML
UML 1.x is greatly influenced by the OMT notations. However, UML 1.x suffers from weak semantic integration. Later, some other concepts were also merged with UML related to the object oriented methods. The issue of weak semantic integration was handled in the UML 2.0's major revision. UML 1.3, 1.4, and 1.5 also followed as revision versions of UML 1.1.
Later, UML 2.1 came into existences without being released as a formal specification. In 2007, the versions and appeared. UML 2.3 was released in May of It was followed by UML in August of UML 2.5 got released in October 2010.
In spite of being better defined than UML 1.5, the state of UML 2.0 is not satisfying enough. It comes with constraints like overloaded notation, lack of precise semantics and also lack the methodological basis like usage types, etc. The development to version 2.0 also extended the set of diagrams, and included 13 types of diagrams:

5. Type of UML diagrams
Structure diagrams show the things in a system being modeled. In a more technical term, they show different objects in a system. Behavioral diagrams shows what should happen in a system. They describe how the objects interact with each other to create a functioning system.

6. Description of UML Diagrams
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. 

7. Description of UML Diagrams
Example
Activity Diagram
Activity diagrams represent workflows in a graphical way. They can be used to describe business workflow or the operational workflow of any component in a system. Sometimes activity diagrams are used as an alternative to State machine diagrams.

8. Description of UML Diagrams
Example
State Machine Diagram
State machine diagrams are similar to activity diagrams, although notations and usage change a bit. They are sometime known as state diagrams or state chart diagrams as well. These are very useful to describe the behavior of objects that act differently according to the state they are in at the moment. The State machine diagram below shows the basic states and actions.

9. Description of UML Diagrams
Example
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.

10. Description of UML Diagrams
Example
Object Diagram
Object Diagrams, sometimes referred to as Instance diagrams are very similar to class diagrams. Like class diagrams, they also show the relationship between objects but they use real world examples. They are used to show how a system will look like at a given time. Because there is data available in the objects, they are often used to explain complex relationships between objects.

11. Description of UML Diagrams
Example
Interaction Diagram
Interaction diagrams are models that describe how a group of objects collaborate in some behavior - typically a single use-case. The diagrams show a number of example objects and the messages that are passed between these objects within the use-case.
Interaction diagrams come in two forms sequence and collaboration diagrams

12. Description of UML Diagrams
Example
Sequence Diagram
Sequence diagrams in UML show how objects interact with each other and the order those interactions occur. It’s important to note that they show the interactions for a particular scenario. The processes are represented vertically and interactions are show as arrows.

13. Description of UML Diagrams
Example
Collaboration Diagram
Simple collaboration diagrams simply number the messages in sequence. More complex schemes use a decimal numbering approach to indicate if messages are sent as part of the implementation of another message. In addition a letter can be used to show concurrent threads.

14. Description of UML Diagrams
Example
Component Diagram
A component diagram displays the structural relationship of components of a software system. These are mostly used when working with complex systems that have many components. Components communicate with each other using interfaces. The interfaces are linked using connectors.

15. Description of UML Diagrams
Example
Deployment Diagram
A deployment diagram shows the hardware of your system and the software in those hardware. Deployment diagrams are useful when your software solution is deployed across multiple machines with each having a unique configuration. Below is an example deployment diagram.

16. Description of UML Diagrams
Example
Package Diagram
As the name suggests, a package diagram shows the dependencies between different packages in a system. 

17. Description of UML Diagrams
Example
Communication Diagram
Communication diagram was called collaboration diagram in UML 1. It is similar to sequence diagrams, but the focus is on messages passed between objects. The same information can be represented using a sequence diagram and different objects.

18. Description of UML Diagrams
Example
Profile Diagram
Profile diagram is a new diagram type introduced in UML 2. This is a diagram type that is very rarely used in any specification.

19. Description of UML Diagrams
Example
Composite Structure Diagram
Depicts the internal structure of a classifier (such as a class, component, or use case), including the interaction points of the classifier to other parts of the system

20. Description of UML Diagrams
Example
Timing Diagram
Timing diagrams are very similar to sequence diagrams. They represent the behavior of objects in a given time frame. If it’s only one object, the diagram is straight forward, but if there are more than one object involved, they can be used to show interactions of objects during that time frame as well.

21. Description of UML Diagrams
Example
Timing Diagram
Timing diagrams are very similar to sequence diagrams. They represent the behavior of objects in a given time frame. If it’s only one object, the diagram is straight forward, but if there are more than one object involved, they can be used to show interactions of objects during that time frame as well.