What are the basic characteristics of object-oriented analysis and design (OOAD)? How does OOAD compare to structured analysis and design (SAD)? For those of you who want to know what aspect of the above mentioned you should post or reply, consider asking yourself about the following questions: What is UML? What are the basic elements? There are several OOAD diagrams under the UML concept. Describe the relationship between the four key OOAD diagramsuse case, class, sequence, and statechart or machine diagrams? What is the purpose of the use-case diagram? Describe the symbols. Why is it the first diagram created in the OOAD approach? What is the difference between include or extend relationships on a use-case diagram? What is the rule for drawing them? What is the purpose of the use-case description? How can it be used to communicate with team members and the user? How do you find classes from the use-case diagram? Give an example. What are the three components of a class? What is the purpose of multiplicities on between classes? What is the difference between generalization or specialization and aggregation relationships on a class diagram? What is the purpose of the sequence diagram? How does it relate to the communication diagram? What is a flow of events or scenarios in a use case? How does it relate to the creation of the sequence diagram? What is the purpose of the statechart or machine diagram? How does it relate to the class? How does the statechart or machine diagram help to accurately design classes? What are packages? How does it help with design and implementation?