UML diagram

1. Use case diagram

They show various activities the users can perform on the system. They model the dynamic aspects of system. It provides users perspective of the system. Actor: An actor is a user of system playing a particular role.

Use case: Use case is particular activity a user can do on the system.

Relationship: Relationship are simply illustrated with a line connecting actors to use cases.

2. Class Diagram

A class diagram describes the types of objects in the system and the various kinds of static relationships that exist among them. i.e., A graphical representation of a static view on declarative static elements. A class is the description of a set of objects having similar attributes, operation, relationships and behaviour.

3. Sequence Diagram

A sequence diagram is unified modelling language (UML) is a kind of interaction diagram that shows how processes operate with one another and in what order. It is a construct of a Message Sequence chart. Sequence diagrams are sometimes called event diagrams, event scenarios, and timing diagrams.Sequence Diagram of Overall Process

Sequence Diagram of Withdrawal from ATM

4. Activity Diagram Activity diagram is another important diagram in UML to describe dynamic aspects of the system. Activity diagram is basically a flow chart to represent the flow form one activity to another activity. The activity can be described as an operation of the system. So the control flow is drawn from one operation to another. This flow can be sequential, branched or concurrent. Activity diagrams deals with all type of flow control by using different elements like fork, join etc.