LEARNING UNIT 3: CHAPTER 8
user-centred design: design techniques that embody the view that the user interface appears to be
the entire system
usability: the degree to which a system is easy to learn and use
human-computer interaction (HCI): a field of study concerned with the efficiency and effectiveness
of user interfaces vis-à-vis computer systems, human-oriented input and output technology, and
psychological aspects of user interfaces
metaphors: analogies between features of the user interface and aspects of physical reality with
which users are familiar
direct manipulation metaphor: metaphor in which objects on a display are manipulated to look like
physical objects (pictures) or graphic symbols that represent them (icons)
desktop metaphor: metaphor in which the visual display is organized into distinct regions, with a
large empty workspace in the middle and a collection of tool icons around the perimeter
document metaphor: metaphor in which data is visually represented as paper pages or forms
dialogue metaphor: metaphor in which user and computer accomplish a task by engaging in a
conversation or dialogue via text, voice, or tools, such as labelled buttons
human-interface objects (HIOs): icons and other objects on a screen that can be manipulated by the
user and cause some action to occur
affordance: when the appearance of a specific control suggests its function
tool tip: brief instructions that pop up when the mouse hovers over a control
, visibility: when a control is visible so that users know it is available
feedback: some visual or audio response by the system in response to a user action
radio buttons: a group of selection items that allows only one item to be selected within the group
check boxes: a group of selection items that allows either none or many items to be selected within
the group
CONSISTENCY
Consistency can be applied to many different aspects of the user interface, as well as to the
application itself. The effectiveness of the user experience is highly dependent on consistency. Users
not only expect consistency across the various screens of an application, but now also anticipate
consistency across applications.
Consistency within and across platforms
Consistency within a suite of applications
Consistency within an application
Consistency versus continuity
Continuity: maintaining a certain level of consistency over time, across multiple releases
user-centred design: design techniques that embody the view that the user interface appears to be
the entire system
usability: the degree to which a system is easy to learn and use
human-computer interaction (HCI): a field of study concerned with the efficiency and effectiveness
of user interfaces vis-à-vis computer systems, human-oriented input and output technology, and
psychological aspects of user interfaces
metaphors: analogies between features of the user interface and aspects of physical reality with
which users are familiar
direct manipulation metaphor: metaphor in which objects on a display are manipulated to look like
physical objects (pictures) or graphic symbols that represent them (icons)
desktop metaphor: metaphor in which the visual display is organized into distinct regions, with a
large empty workspace in the middle and a collection of tool icons around the perimeter
document metaphor: metaphor in which data is visually represented as paper pages or forms
dialogue metaphor: metaphor in which user and computer accomplish a task by engaging in a
conversation or dialogue via text, voice, or tools, such as labelled buttons
human-interface objects (HIOs): icons and other objects on a screen that can be manipulated by the
user and cause some action to occur
affordance: when the appearance of a specific control suggests its function
tool tip: brief instructions that pop up when the mouse hovers over a control
, visibility: when a control is visible so that users know it is available
feedback: some visual or audio response by the system in response to a user action
radio buttons: a group of selection items that allows only one item to be selected within the group
check boxes: a group of selection items that allows either none or many items to be selected within
the group
CONSISTENCY
Consistency can be applied to many different aspects of the user interface, as well as to the
application itself. The effectiveness of the user experience is highly dependent on consistency. Users
not only expect consistency across the various screens of an application, but now also anticipate
consistency across applications.
Consistency within and across platforms
Consistency within a suite of applications
Consistency within an application
Consistency versus continuity
Continuity: maintaining a certain level of consistency over time, across multiple releases
