The moment-by-moment interaction between people and designed outcomes.
Design outcomes exist to be used. When someone orders a blood test, reads a package of burritos, shouts through a bullhorn, or uses an e-reader, they interact with a design. These interactions reveal ways design outcomes are intuitive and helpful for completing activities, and they sometimes reveal frustrations and breakdowns in design. Examining products, services, and systems through interactions helps designers better understand the user experience.