1) UX design focuses on understanding user needs and designing intuitive user flows, while UI design adds visual design elements like colors and typography.
2) A UX designer researches user needs through interviews and testing, then designs user flows. A UI designer takes those designs and adds visual design elements.
3) Both are important - UX ensures a product is useful while UI ensures it is visually appealing and on-brand. They work together with UX informing overall design and UI realizing that design.
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