List any three (3) benefits of usability. What are the three goals of usability? Briefly, explain any three expert-based usability evaluation methods. Briefly, explain any three (3) user-based usability evaluation methods.

Three benefits of usability are:
I. Improved user satisfaction: When a system is easy to use, users are more likely to enjoy their experience and be satisfied with the product.
II. Increased efficiency: A usable system allows users to complete tasks more quickly and with less effort, leading to higher productivity.
III. Reduced errors: Good usability design helps prevent users from making mistakes and provides clear ways to recover if errors do occur.

The three main goals of usability are:
I. Effectiveness: This refers to the accuracy and completeness with which users achieve specific goals.
II. Efficiency: This measures the resources expended in relation to the accuracy and completeness with which users achieve goals (e.g., time taken, mental effort).
III. Satisfaction: This describes the comfort and acceptability of the work system to its users and other people affected by its use.

Three expert-based usability evaluation methods are:
I. Heuristic Evaluation: In this method, usability experts evaluate an interface against a set of established usability principles (heuristics) to identify potential problems.
II. Cognitive Walkthrough: Experts simulate a user's thought process step-by-step through a task to identify potential problems a new user might encounter, focusing on learnability.
III. Expert Review/Critique: Usability specialists examine an interface and provide feedback based on their extensive knowledge of usability principles and experience with similar systems.

Three user-based usability evaluation methods are:
I. Surveys/Questionnaires: Users are asked to provide feedback on their experience with a system through structured questions, often using rating scales or open-ended responses.
II. Usability Testing: Actual users perform predefined tasks with the system while researchers observe their behavior, record their interactions, and note any difficulties or successes.
III. Observation: Researchers directly watch users interact with a system in their natural environment or a controlled setting to understand their behavior, workflows, and challenges without direct intervention.