Motivation Usability problems that the heuristic tries to avoid. 1. Visibility of System Status Conformance Question Are users kept informed about system progress with appropriate feedback within reasonable time? Evidence of Conformance...
moreMotivation Usability problems that the heuristic tries to avoid. 1. Visibility of System Status Conformance Question Are users kept informed about system progress with appropriate feedback within reasonable time? Evidence of Conformance Necessary evidence must be identified through analysis of individual tasks. Motivation Feedback allows the user to monitor progress towards solution of their task, allows the closure of tasks and reduces user anxiety. Description of Heuristic Evaluation 2 2. Match between system and the real world Conformance Question Does the system use concepts and language familiar to the user rather than system-oriented terms. Does the system use real-world conventions and display information in a natural and logical order? Evidence of Conformance Necessary evidence must be identified through user studies (or through assumptions about users!), and through the analysis of individual tasks. Motivation A good match minimises the extra knowledge required to use the system, simplifying all task action mappings (re-expression of users intuitions into system concepts). 3. User control and freedom Conformance Question Can users do what they want when they want? Evidence of Conformance Necessary evidence takes the form of a diverse set of design features, for example "undo and redo", clearly marked exits etc. Motivation Quite simply, users often choose actions by mistake. 4. Consistency and Standards Conformance Question Do design elements such as objects and actions have the same meaning or effect in different situations? Evidence of Conformance Necessary evidence must be identified through several analyses (consistency within system, conformance to style guides, consistency across task methods). Motivation Consistency minimises user knowledge required to use system by letting users generalise from existing experience of the system or other systems. Description of Heuristic Evaluation 3 5. Error prevention Conformance Question Can users make errors which good designs would prevent? Evidence of Conformance Necessary evidence must be identified through analysis of individual tasks and of system details (e.g. adjacency of function keys and menu options, discriminability of icons and labels). Motivation Errors are the main source of frustration, inefficiency and ineffectiveness during system usage. 6. Recognition rather than recall Conformance Question Are design elements such as objects, actions and options visible? Is the user forced to remember information from one part of a system to another. Evidence of Conformance Necessary evidence must be identified through analysis of individual tasks. Motivation Forcing users to remember details such as command and file names is a major source of error. Recognition minimises user knowledge required to use the system. Summarising available commands or options may allow the user to guess their meaning or purpose. 7. Flexibility and efficiency of use Conformance Question Are task methods efficient and can users customise frequent actions or use short cuts? Evidence of Conformance Necessary evidence must be identified through analysis of individual tasks, and the presence of design features such as keyboard accelerators etc. Motivation Inefficient task methods can reduce user effectiveness and cause frustration. 8. Aesthetic and minimalist design Conformance Question Do dialogues contain irrelevant or rarely needed information? Description of Heuristic Evaluation 4 Evidence of Conformance Necessary evidence must be identified through analysis of individual tasks. Motivation Cluttered displays have the effect of reducing search times for commands or users missing features on the screen. Users unfamiliar with a system often have to find an action to meet a particular need-reducing the number of actions available could make the choice easier. 9. Help users recognize, diagnose and recover from errors Conformance Question Are error messages expressed in plain language (no codes), do they accurately describe the problem and suggest a solution? Evidence of Conformance Necessary evidence must be identified through analysis of error messages. Motivation Errors are the main source of frustration, inefficiency and ineffectiveness during system usage. The first ten heuristics were originally suggested by Jakob Nielsen. These materials have been developed for use on UK EPSRC project no. GR/K82727 (Extending HCI Design Principles and Task Analysis for Software and Data Visualisation) by Darryn Lavery, Gilbert Cockton and Malcolm Atkinson. A structure has been applied to the heuristics, and to the best of our intentions we have kept the original meanings of the individual heuristics. The structure and any unintended changes to the meanings remain the responsibility of the authors and not Jakob Nielsen.