UX/UI Exam

visibility of system status (heuristic evaluation)

the system should always keep users informed about what is going on, through appropriate feedback within reasonable time.

Match between system and the real world (heuristic evaluation)

the system should speak the user’s language, with words, phrases and concepts familiar to the user, rather than system-oriented terms. Follow real-world conventions, making information appear in a natural and logical order.

User control and freedom (heuristic evaluation)

Users often choose system functions by mistake and will need a clearly marked "emergency exit" to leave the unwanted state without having to go through an extended dialogue. Support undo and redo.

Consistency and standards (heuristic evaluation)

Users should not have to wonder whether different words, situations, or actions mean the same thing. Follow platform conventions.

Error prevention (heuristic evaluation)

Even better than good error messages is a careful design which prevents a problem from occurring in the first place. Either eliminate error-prone conditions or check for them and present users with a confirmation option before they commit to the action.

Recognition rather than recall (heuristic evaluation)

Minimize the user's memory load by making objects, actions, and options visible. The user should not have to remember information from one part of the dialogue to another. Instructions for use of the system should be visible or easily retrievable whenever appropriate.

Flexibility and efficiency of use (heuristic evaluation)

Accelerators—unseen by the novice user—may often speed up the interaction for the expert user such that the system can cater to both inexperienced and experienced users. Allow users to tailor frequent actions.

Aesthetic and minimalist design (heuristic evaluation)

Dialogues should not contain information which is irrelevant or rarely needed. Every extra unit of information in a dialogue competes with the relevant units of information and diminishes their relative visibility.

Help users recognize, diagnose, and recover from errors (heuristic evaluation)

Error messages should be expressed in plain language (no codes), precisely indicate the problem, and constructively suggest a solution.

Help and documentation (heuristic evaluation)

Even though it is better if the system can be used without documentation, it may be necessary to provide help and documentation. Any such information should be easy to search, focused on the user’s task, list concrete steps to be carried out, and not be too large.

Affordance

refers to the relationship between a physical object and a person. It is a relationship between the properties of an object and the capabilities of the agent that determine just how the object could possibly be used

ex:

• A chair affords (“is for”) support and, therefore, affords sitting. Most chairs can also be carried by a single person (they afford lifting), but some can only be lifted by a strong person or by a team of people. If young or relatively weak people cannot lift a chair, then for these people, the chair does not have that affordance, it does not afford lifting.”

• Glass affords transparency. At the same time, its physical structure blocks the passage of most physical objects. As a result, glass affords seeing through and support, but not the passage of air or most physical objects (atomic particles can pass through glass). The blockage of passage can be considered an anti-affordance—the prevention of interaction

• . Knobs afford turning, pushing, and pulling. Slots are for inserting things into. Balls are for throwing or bouncing. Perceived affordances help people figure out what actions are possible without the need for labels or instructions. 

Signifier

Refers to any mark or sound, any perceivable indicator that communicates appropriate behavior to a person. the signaling component of affordances is signifiers. Use to ensure good discoverability and feedback

ex:

• Arrows and icons on a screen is a signifier 

Discoverability

determine what actions are possible and the current state

Conceptual model

provide the information needed to create a good conceptual model generating understanding and a sense of control. Enhances discoverability and evaluations of results

ex: a file folder icon on a computer represents physical file storage

Constraints

physical, logical, semantic, and cultural constraints guide actions and ease interpretation

ex: Graying out unavailable menu options in software.

Feedback

full and continuous about the result of actions and the current state. New states following an action are obvious.

ex: Clicking a button changes its color to show it has been pressed.