Nielsen’s Five Components of Usability

Jakob Nielsen’s five-component model, detailed in his seminal 1993 book “Usability Engineering,” provided a practical and influential 框架 for designers and evaluators. Unlike the more formal ISO definition, Nielsen’s model is more directly applicable to the design and inspection of user interfaces. ‘Learnability’ is crucial for new users; an interface with good learnability allows someone to become productive quickly. ‘Efficiency’ targets expert users, ensuring that the system doesn’t hinder them once they’ve mastered it, often through features like shortcuts or advanced commands. ‘Memorability’ addresses the casual user who may return to the system after a long break. The interface should be easy to remember, minimizing the need for retraining. The ‘Errors’ component is not just about preventing errors but also about making them less catastrophic and providing clear ways for users to recover. A good system might use confirmation dialogs for destructive actions or offer a robust “undo” feature. Finally, ‘Satisfaction’ captures the subjective element of the user’s experience, acknowledging that even an efficient and error-free system can be frustrating or unpleasant to use. This model’s strength lies in its intuitive nature and its direct translation into actionable design goals and evaluation criteria, making it a cornerstone of practical usability work for decades.