What Is Interaction Design

Interaction design (IxD) is the branch of user experience design that illuminates the relationship between people and the interactive products they use. While interaction design has a firm foundation in the theory, practice, and methodology of traditional user interface design, its focus is on defining the complex dialogues that occur between people and interactive devices of many types--from computers to mobile communications devices to appliances.

Interaction designers strive to create useful and usable products and services. Following the fundamental tenets of user-centered design, the practice of interaction design is grounded in an understanding of real users--their goals, tasks, experiences, needs, and wants. Approaching design from a user-centered perspective, while endeavoring to balance users' needs with business goals and technological capabilities, interaction designers provide solutions to complex design challenges, and define new and evolving interactive products and services.

The success of products in the marketplace depends on the design of high-quality, engaging interactive experiences. Good interaction design

effectively communicates a system's interactivity and functionality
defines behaviors that communicate a system's responses to user interactions
reveals both simple and complex workflows
informs users about system state changes
prevents user error

While interaction designers often work closely with specialists in visual design, information architecture, industrial design, user research, or usability, and may even provide some of these services themselves, their primary focus is on defining interactivity.

The discipline of interaction design produces products and services that satisfy specific user needs, business goals, and technical constraints. Interaction designers advance their discipline by exploring innovative design paradigms and technological opportunities. As the capabilities of interactive devices evolve and their complexity increases, practitioners of the discipline of interaction design will play an increasingly important role in ensuring that technology serves people's needs.

In summary, interaction design defines

the structure and behaviors of interactive products and services
user interactions with those products and services