The article discusses how human-computer interfaces are currently understood and suggests a new model to better grasp user interfaces. Many new ways of interacting with technology have emerged in recent years, but our understanding of interfaces is still rooted in older concepts. The review found that current textbooks lack a consistent definition of interfaces and often focus on outdated ideas. The proposed model includes five key concepts to help us better understand interfaces. The author also shares examples of how this model has been used in teaching.