Interaction design (IxD) is the practice of defining how users engage with a digital product through behavior, feedback, and motion. It focuses on shaping the interactive moments between user and interface—such as clicks, swipes, transitions, hover states, microinteractions, and response timing.
The goal of interaction design is to make experiences feel intuitive, responsive, and human. It ensures that each action has a clear reaction, helping users understand what’s happening, what’s possible, and what comes next. Interaction designers work closely with UX and UI teams to choreograph these behaviors, often using prototypes and motion specs to communicate intent.