Lesson 4 System Development Methodologies

 The lesson 4 topic was all about System Development Methodologies. 

The first part of the discussion was a brief introduction of different types of software and those are system software, application software, freeware, commercial, open source and in-house software. System Software controls a computers internal functioning, through an operating system, and also controls such peripherals as monitors, printers, and storage devices. System software also contain a lots of principle.

The lesson 4 was mostly about software development life cycle (SDLC) and system methodology. There are five system methodology that discussed by our professor.

So what is SDLC? From what I understand the basic idea of the systems development life cycle is that there is a well-defined process by which an application is conceived, developed and implemented. It is important to have an SDLC in place as it helps to transform the idea of a project into a functional and completely operational structure. The most important benefit of the SDLC is that it provides a degree of control of the development process and guarantees that all the estimated specifications are met by the software framework. SDLC can be compare to constructing a building the phases and logic of step by step are pretty much the same. So the every phases of SDLC are very important for developing a system. One of the problem with SDLC is the lack of understanding a client can cause wasting a lot of time, since the moment that the project is on the phase of implementation then client will mostly complain because the lack of understanding the client.

There are five system methodology that discussed by our professor.

-Waterfall model is a sequential activity based process in which each phase in the SDLC is performed sequentially. One of the benefits of the waterfall model is that it is quick to use and comprehend, sets stability criteria and is useful for management control. There are also a of drawback of the waterfall model and one of this is that it can offer a false impression of development, all specifications must be understood in advance to avoid mistakes, and there is a little chance for customers to preview the system.

-Rapid Application Development is a system development software development that focuses on rapidly constructing a software working model, providing user input and then using that feedback to update the working model.

-Prototyping model is the construction method that shows the characteristics of a product, service or system proposed. It also provides the foundation for the final system or software to be created.

-Agile Software is focused on a gradual and iterative approach, where requirements and solutions grow through cooperation between cross-functional teams that are self-organized. It is also open to evolving overtime conditions and promotes the end user's frequent feedback.

-Iterative Development, it is a system analysis and design approach that in successive iterations completes the entire information system.

Developers chooses what model to use depending on the system they are working because every model has its advantage and disadvantages.