Definition
User experience (UX) describes the entire process and overall feeling a person has when using a product, including usability, efficiency and emotional response. Cognitive scientist Don Norman popularized the term in the 1990s.
How it works
UX design starts from understanding users and their tasks, then iterates through information architecture, interaction flows, prototypes and usability testing. The goal is that users can accomplish their goals smoothly and feel clear and satisfied along the way.
Usage
Websites, applications, hardware and even service processes all involve UX. Product teams commonly assess experience quality with methods such as usability testing and user interviews.
Related and confusable terms
UX and UI are often conflated: the UI is the interface users touch, while UX spans the whole journey from discovering a product to completing a goal. GUI, as the graphical form of an interface, is one factor that shapes UX but is not UX itself.