design principle Flashcards
visibility
providing cues in the user interface that helps users recognise possible actions and how to do them
affordances
what we can do with things in our environment
the relationship between properties of an object and the capabilities of the user that determines how the object could be used
physical affordances
properties of an object that afford certain actions
what is an example of a physical affordance
buttons affording pressing
affordances of objects
some objects invite actions and tell us what to do with them
demand character
certain designs demand us to interact in a certain way
perceptual affordances
affordances of software that include all actions possible for the user via the user interface
action possibilities that the user can immediately recognise
what is an example of a perceptual affordance
buttons looking clickable
signifiers
indicators or signals that announce affordances but can also exist on their own
what is an example of an affordance of an object
door handle = pull
sensory indicators
perceived without thinking
icons/sounds/animations
based on a learned meaning of the signifier
cognitive indicators
require more processing
labels and instructions
how do signifiers show what’s not possible
greyed-out options
constraints
limit the actions the user can perform
what is an example of a constraint
date picker to avoid format errors
what are the 4 types of constraints
physical
semantic
logic
cultural
physical constraints
hardware limiting actions
e.g. only being able to join cables in one way
semantic constraints
thinking about what makes sense based on the situation
e.g. greyed out options
logic constraints
only one possibility for the action so the user goes with that one
cultural constraints
apply cultural conventions
e.g.red = stop
what are the 2 forcing functions that constraints can use to avoid errors
lock in prevents you from leaving a process prematurely
lock out prevents you from completing an action
feedback
provides feedback on actions and the status of the system and interactions in real time
which design principles prevent the gulf of execution
constraints
affordances
visibility
signifiers
which design principles prevent the gulf of evaluation
feedback
how can delays been shown when receiving feedback
loading circle or progress bar
feedback on errors
users should be able to understand all error messages in order to get back on track
what are the 6 types of design rules
generality
authority
golden rules
style guides
standards
design patterns
generality
do they apply to many design situations or are they specific
authority
how important it is that you apply the guidance
what are the 8 golden rules
strive for continuity
seek universal usability
offer informative feedback
design dialogues to yield closure
prevent errors
permit easy reversal of actions
keep users in control
reduce short term memory load
strive for consistency
the ui should be consistent within itself but also across other apple that the user may come across
what are the 5 types of consistency
internal
external
syntactic
semantic
terminological
what happens when a ui isn’t consistent
it can be hard for the user to know what the effect of their actions will be
internal consistency
within the same application
external consistency
across applications
syntactic consistency
organizational
e.g. buttons should be displayed the same way each time
semantic consistency
the meaning of things stay the same
terminological consistency
words
e.g. “ok” always being the label of the button for ok
seek universal usability
recognising the different types and contexts of users
e.g. experts vs novices
offer informative feedback
there should be appropriate feedback in response to each action
design dialogues to yield closure
ensuring that interactions between the user and the system have a clear beginning middle and end
prevent errors
help the user stay on track and not get to the point of an error
permit easy reversal of actions
providing undo functions
keep the user in control
the user should be feel like the system is responding to their actions and they’re controlling it
reduce short term memory load
the system should remember things for the user and they shouldn’t have to input int=formation multiple times
standards
established guidelines and best practices
what are the 4 principles of usability according to wcag
perceivable
operable
understandable
robust
perceivable
information must be presented in a way that users can perceive it
operable
components and navigation must be operable
understandable
info should be understandable
should help users avoid mistakes
robust
must be robust enough to be interpreted reliably by user agents including assistive technologies
design patterns
recurring solutions that solve common design problems
style guides
a design standard for specific products platforms and libraries that creates guidance for developers
what do design patterns describe
a common problem
context it appears in
the solution and rationale
examples of the pattern being illustrated
what do style guides define
what the ui should look like
how its operated
hoe it reacts to an input
what it feels like
