Usability Categories And Heuristics

A Heuristic evaluation is done as a systematic inspection of a user interface design for usability. The goal of heuristic evaluation is to find the usability problems in the design so that they can be attended to as part of an iterative design process. Heuristic evaluation involves having a small set of evaluators examine the interface and judge its compliance with recognized usability principles (the "heuristics").
http://www.useit.com/papers/heuristic/

1. Understandability

• Wording: clear, appropriate wording; fits the target group, lack of foreign and technical terms?
• Information: clear, sufficient, available everywhere where neces-sary, fits the target group?
• System feedback (error messages, confirmations): pre-sent/available where necessary, clear, sufficient, fits the target group?
• Navigational elements (navigation elements, buttons, icons, sym-bols): complete, clear, fitting?
• Information architecture: classification of topics and content to categories clear and comprehendible?
• Input: Clear which input is expected; input processing unit must tolerate and cope with input errors.
• Process: The order of the steps in a process is clear und compre-hendible, appears logical and complete.
• Concept: Concept is clearly communicated and can be easily grasped.

2. Recognisability

• Legibility: Typeface allows easy reading, font size is sufficiently large and can be easily recognized, font colour contrasts the back-ground well.
• Visibility; Design and Layout clarity*: clear design, appropriate use of colours; fundamental information, content, links, buttons and symbols can be quickly spotted and easily recognized. The applica-tion lacks elements that divert from the main content or key aspects of the application.

3. Navigation & Orientation

• Navigation within the application or in a process does not limit, but provides all possible/necessary degrees of freedom. Back and for-ward navigation is always possible.
• Navigation to the main menu is consistently available.
• All required links are present and functioning as intended or ex-pected by users.
• Structure, layout and design allow the user to unambiguously know
  1. his current position within an application,
  2. how he arrived at this point and where he came from and
  3. and how he can continue. The application is equipped with tools or features, such as breadcrumbs (web) and highlighting of menu items that aid orientation.

4. Handling

• Manipulation of elements is easy and obvious.
• Reaching a goal is from an operational perspective simple and straight-forward.

5. Control

• Easily recognizable system status / transparency: Information about what the system is currently doing and about what the user can presently do is readily presented. Clear messages informing about the beginning and end of a process are available. The system unambiguously prompts the user when he can/should do something.
• Meets expectations: The application acts/reacts as the user ex-pects it to. It meets general conventions.
• System Feedback: System messages are available.
• Critical Information (e.g. General Terms and Conditions, Prices) can be quickly and easily loaded.

6. Consistency

• Buttons, links, labels, titles or design elements are presented con-sistently and/or conform to style-guides. Learning is simplified by eliminating unnecessary trial and error.
• Meaning and function of important elements is clear, unambiguous and can be quickly deduced due to their resemblance in appearance and/or behaviour to other objects of equal quality or category.

7. Performance

• Menus, windows and screens load quickly.
• Usage is simplified by the systems’ quick responses. Slow and unre-sponsive systems can make users insecure.

8. Technology

• Compatibility with other systems works seamlessly.
• Output quality is of good quality (e.g. Videostreams, Pics).

9. Errors

• The application is free from spelling mistakes, bugs, bogus output.

10. Utility

• The application is complete. Content, features and functions that are de-manded by users or by the task are all available.