User interface (UI) design is the visual and interactive discipline that defines how users experience a product’s surface—everything they see, touch, and interact with on-screen. It involves crafting layouts, choosing color palettes, designing typography systems, shaping icons and buttons, and defining interactive states like hovers, clicks, or transitions.
More than just aesthetics, UI design ensures that a product’s interface is clear, accessible, and aligned with both the brand identity and user expectations. It works hand-in-hand with UX design: where UX defines the journey, UI brings that journey to life visually and emotionally.
UI designers focus on creating consistency, hierarchy, and usability across screens and devices. They build design systems, component libraries, and visual guidelines that scale. The best UI design balances form and function—delivering an interface that feels effortless, engaging, and purposeful.