UI (User Interface) Design and UX (User Experience) Design are closely related but serve different purposes in product development: UI Design focuses on the look and feel of a product — how the interface looks, including colors, typography, buttons, layout, and visual elements. It's about creating visually appealing and consistent designs. UX Design is about the overall experience a user has when interacting with a product. It involves research, user flows, wireframing, usability testing, and ensuring the product is intuitive, efficient, and enjoyable to use.