What are the main differences between structured analysis, O-O, and agile development methods?Which method do you think is best, and why?

What will be an ideal response?

While structured analysis regards processes and data as separate components, object-oriented (O-O) analysis combines data and the processes that act on the data into things called objects. O-O analysis uses object models to represent data, behavior, and by what means objects affect other objects. By describing the objects (data) and methods (processes) needed to support a business operation, a system developer can design reusable components for faster system implementation and decreased development cost. Many analysts believe that, compared with structured analysis, O-O methods are more flexible, efficient, and realistic in today’s dynamic business environment.
As noted in the suggested answer to Review Question 9, agile development methods have attracted a wide following and an entire community of users. Agile methods typically use a spiral model, which represents a series of iterations, or revisions, which are based on user feedback. Proponents of the spiral model believe that this approach reduces risks and speeds up software development. Analysts should recognize that agile methods have advantages and disadvantages.
By their nature, agile methods allow developers to be much more flexible and responsive, but can be riskier than more traditional methods. For example, without a detailed set of system requirements, certain features requested by some users might not be consistent with the company’s larger game plan. Other potential disadvantages of adaptive methods can include weak documentation, blurred lines of accountability, and too little emphasis on the larger business picture. Also, unless properly implemented, a long series of iterations might actually add to project cost and development time.