Recalling items from scratch is harder than recognizing the correct option in a list of choices because the extra context helps users retrieve information from memory.| Nielsen Norman Group
The interaction cost is the sum of efforts — mental and physical — that users must deploy in interacting with a site in order to reach their goals.| Nielsen Norman Group
Users are often distracted from the task at hand, so prevent unconscious errors by offering suggestions, utilizing constraints, and being flexible.| Nielsen Norman Group
Across many tasks, learning curves show an initial learning period, followed by a plateau of optimal efficiency.| Nielsen Norman Group
Jakob Nielsen's 10 general principles for interaction design. They are called "heuristics" because they are broad rules of thumb and not specific usability guidelines.| Nielsen Norman Group