The spiral model combines the idea of ​​iterative development with the systematic and controlled aspects of the waterfall model. The spiral model has four phases. A software project goes through these phases repeatedly in iterations called Spirals. This means that the product is released gradually. Say no to plagiarism. Get a tailor-made essay on “Why Violent Video Games Should Not Be Banned”? Get an original essay The identification phase begins with collecting business requirements into the basic spiral. In subsequent spirals, as the product matures, identification of system requirements, subsystem requirements and unit requirements is carried out during this phase. Proof of concept includes identifying, estimating, and monitoring technical feasibility and management risks, such as schedule delays and cost overruns. After testing the release, at the end of the first iteration, the customer evaluates the software and provides feedback. This phase also includes understanding the system requirements through continuous communication between the client and the system analyst. The design phase begins with conceptual design in the base spiral and involves architectural design, logical module design, physical product design, and final design in the later spirals. The application architecture is designed at this stage i.e. the structure of the application e.g. UI features like colors, text, tabs, buttons and links. After that each module of the application is designed and finally the whole system is designed in the latest version. The customer provides feedback on this design during the evaluation phase at the end of the iteration. The build phase refers to the production of the actual software product at each spiral. In the basic spiral, the product is implemented by software developers, who code the application so that it works correctly. Developers should follow the design provided by the designers. Another version is created later in development, so that new implementations can be provided that might be more efficient. The first build is used as a backup if the second build fails. The version is tested during the evaluation phase. The evaluation phase involves managing risks in the application used to contain and mitigate threats in the product and also testing the operation of the application, which is done to make the code more efficient and reduce errors found in the construction of the product. The customer provides feedback on the design and construction of the system, to see how the product development is carried out. The spiral model is applied when: When the budget is low and risks need to be assessed. The project is medium to high risk. The customer is unsure of their requirements. The requirements are complex and must be evaluated for clarity. Significant changes are expected in the product during the development cycle. Advantages of the spiral model: Requirements can be changed. Promotes the use of prototypes. Requirements can be defined more precisely. .Users can see the system in the early stages of development. Development can be divided into modules and difficult modules can be developed earlier. Disadvantages of the model: The end of the project may not be known early. Management is more complex. The spiral can be activated indefinitely. Not suitable for small or low risk projects. Waterfall Among the.