1. What is Iterative Design?

Definition: Iterative design is a repetitive process of designing, testing, analyzing, and refining a system until it meets usability, functionality, and user satisfaction goals.

Key Idea: Instead of designing the system perfectly in one attempt, designers continuously improve the design based on feedback and evaluation.

Purpose:

• Reduce usability problems
• Incorporate real user feedback
• Adapt to changing requirements and constraints

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2. What is Prototyping?

Definition: Prototyping is the creation of a preliminary model of a system that allows users and designers to visualize, explore, and test ideas before final development.

Key Idea: A prototype is a working or visual representation of the system, which can be low-fidelity (sketches) or high-fidelity (interactive software).

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3. Relationship Between Iterative Design and Prototyping

• Prototypes are tools for iterative design.
• Iterative design is the process that guides the repeated creation, testing, and refinement of prototypes.
• Together, they ensure the final system aligns with user needs, tasks, and usability goals.

Iterative Prototyping Cycle:

1. Plan: Identify design goals and target user tasks
2. Design: Create a prototype (low or high fidelity)
3. Test: Conduct usability testing with users
4. Analyze: Collect feedback and identify problems
5. Refine: Improve design based on feedback
6. Repeat: Cycle continues until usability goals are met

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4. Types of Prototypes

Type	Fidelity	Purpose	Example
Paper Prototype	Low	Test layout and navigation	Hand-drawn sketches of screens
Wireframe	Low-Medium	Test structure and flow	Digital layout without styling
Interactive Prototype	Medium-High	Test interaction and navigation	Figma, Adobe XD, or InVision clickable screens
Functional Prototype	High	Test real system functionality	Beta version of software

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5. Benefits of Iterative Design and Prototyping

• Early Detection of Problems: Identify usability issues before full-scale development
• Cost-Effective: Reduces cost of fixing errors after deployment
• User-Centered: Involves real users in evaluating and improving the design
• Encourages Creativity: Allows experimentation without high risk
• Continuous Improvement: Leads to a more usable, efficient, and satisfying system

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6. Best Practices

• Start with low-fidelity prototypes to quickly test ideas
• Include real users in testing as early as possible
• Focus on key tasks and user goals first
• Iterate frequently and incrementally
• Document feedback, changes, and rationale for design decisions

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Key Takeaways

• Iterative design emphasizes continuous improvement based on user feedback and testing.
• Prototyping provides a tangible way to explore and validate design ideas.
• Together, they create a user-centered, efficient, and effective interaction design process.