Incremental Development Model

The incremental development model is a strategy where software is developed gradually and according to a fixed schedule. During each phase, a part of the system is developed and integrated into the already existing system.

1. Requirements Analysis: In the first stage of the incremental model, system requirements are defined. The goal of this phase is to understand the software's functionality and identify what features the system must have.
2. Design and Development: This phase focuses on designing the system architecture and initiating the development process. The incremental model allows new features to be added sequentially, making each finished part a functional addition to the system.
3. Testing: Each developed function is tested to ensure it works correctly. Every added part is tested and verified beforehand to ensure the system's reliability.
4. Implementation: In the implementation phase, final coding and functionality testing are performed. Once the system is ready, final tests are conducted before the system is fully deployed and enhanced.

The incremental development model is based on sequential stages, where each new stage builds upon the previous one and adds new features to the system. All stages focus on specific tasks, including requirement definition, system design, software development, testing, and final implementation.

Iterative Development Model

The iterative development model is a strategy where software development occurs repeatedly through iterations, where each iteration allows enhancement and improvement based on previous experience.

1. Requirements Analysis and Planning: At the beginning of the first iteration, core system requirements are defined. Initial specifications are created, and development priorities are set to start working iteratively.
2. Design and Prototyping: Next, the system architecture is designed, and early prototypes are created. During each iteration, the architecture is developed and improved, and new components are added, allowing for early user feedback.
3. Development and Testing: Each iteration includes development, testing, and bug fixing. After adding new functionality, thorough testing is conducted to ensure system reliability and stability.
4. Feedback and Improvement: At the end of the iteration, feedback is collected from users and clients, based on which necessary changes are made. This iterative approach enables continuous improvement and adjustment of the system to meet changing requirements.

The iterative development model is based on a repeated approach, where each iteration allows improving and enhancing the system based on prior experience. All phases focus on constant feedback, analysis, software development, and refinement to ultimately achieve a stable and high-quality system.

Difference Between Incremental and Iterative

Iterative Development

1. Focus is on improvement.
2. You start with something simple (a prototype, rough version) and improve/refine it with each iteration.
3. The goal is to learn, experiment, and produce increasingly better versions based on user feedback.
4. Example: We build a simple app that only displays a list. In the next iteration, we add the ability to edit the list. Then sorting. Then search. Each iteration improves the existing functionality.

Incremental Development

1. Focus is on adding new functionality.
2. You start with a small part of the system and gradually add new parts step-by-step.
3. Each new increment means new functionality that could be used independently.
4. Example: First, we create user login. Then we add a profile page. Then messaging. Each new part is a new piece (increment) that expands the system's capabilities.