User:Natasa Siencnik/notes/gentner/: Difference between revisions

Revision as of 19:31, 23 October 2010

Abstract

Don Gentner / Jakob Nielson: The Anti-Mac Interface. In: Communications of the ACM. August 1996, Vol. 39, N°8.

Introduction

Alternative Interfaces
- human interface is stuck, very little innovation in interface design anymore
- user has settled on the WIMP (windows, icons, menus, pointer) model
- violating basic assumptions as useful mental exercise to find new concepts
- article explores possible types of interfaces that could result in such a violation
- focus on Macintosh interface as prime example of current interface paradigm
Macintosh Design
- designed for naive users without any previous computer experience
- targeted at a narrow range of applications (office work, entertainment, multimedia)
- weak computational resouces (computer with 128KB RAM, 400KB storage device, printer)
- supported by poor communication channels (screen, keyboard, mouse)

Human Interface Design Principles

based on fundamental principles of human-computer interaction
how do these principles limit the computer-human interface?

Metaphors from familiar noncomputer world
- computer files represented as documents in paper folders placed on desktop
- files deleted by dragging them to the trash can
- trying to overcome the limitations of the desktop metaphor (rooms, buildings, village)
- automobiles have developed their own interfaces without metaphors based on horses
Problems with Metaphors
- target domain has features not in the source domain (e.g. replace command in text editor)
- source domain has features not in the target domain (e.g. marking of typewriters)
- some features exist in both domains but work differently (e.g. white space as character)
Trash Can Metaphor
- single-trash-can metaphor has led to asystem that fails to meet user's needs
- to avoid the confusion of multiple trash cans in the interface, all trash cans are combined
- when user empties the trash to create room on a floppy disk, both trashe cans are deleted
- this is a limitation that does not serve the user's real needs
Desktop Metaphor
- save training time by taking advantage of having learned to operate a traditional office
- next generation of users will make their learning investments with computers
Direct Manipulation
- users interact directly with objects in the interface (e.g. drag and drop a document)
- user cannot group a related series of basic actions into one high-level action
See-and-Point
- users interact with computer by pointing at the objects they see on the screen
- we have lost all power of language, and cannot talk about objects that are not visible (yet)
- utilize more of the power of language to communicate more prececly
Consistency
- difficult to aply in real situation with wide array of conflicting things
- learning will be reduced if objects with similar function always look / behave alike
- in real life we have a wide range of appearances and they can still be easily recognizable
WYSIWYG
- what you see is what you get > document on the screen will look the same when printed
- problem that it is usually equivalent to WYSIATI (what you see is all there is)
- WYSIWYG document only shows final printed representation, not the user's intentions
- Standard Generalized Markup Language (SGML) preserves semantic meaning
- might be useful to have a different representation whe npreparing the document
- electronic information should be modularized and enabled to link to backup information
User Control
- many situations where we do not want to be in control > delegate to machines
- even if control is desirable, full control is becoming impossible with networked computers
Feedbakc and Dialog
- computer interface should provide the user with clear and immediate feedback on actions
- delegation of sequence of activities to an agent or encapsulated in a script
- then tehre is no longer a need for detailed and continuous feedback
Forgiveness
- user actions should generally be reversible and users should be warned of data loss
- computer needs to build a deeper model of our intentions and history
Perceived Stability
- elements in the computer interface should not be changed without user's involvement
- but deviding control between the user and the computer or networked computers
- stability can be boring
Aesthetic Integrity
- graphic design of the interface should be simple, clean, and consistent
- if compters could communicate with richer langugage, look would be less important
- richness can increase usability by making it easier to distinguish
Modelessness
- computer interface should not have distinct modes that restrict the user's actions
- users should be able to perform any task at any time
- problem of modelessness > user cannot cope with everything at once

Anti-Mac Interface

Central Role of Language
- language lets us refer to things not immediately present, potential actions
- encapsulate complex groups of objects or actions and refer to them with single name
- ability to deal with imprecise language will increase the computer's flexibility
- command line interfaces have some of the advantages of language
- command line interfaces have rich syntactic structure to form complex commands
- but only a limited number of commands and cannot tolerate synonyms, misspellings
Richer Internal Representation of Objects
- current interfaces have acces to very little information about the used objects
- the only information about a file may be its name, size, and modification date,
- the type of data it contains, and the application that created it
- but it could include its authors, topic matter, keyword, importance, relations
More Expressive Interface
- richer internal representation of objects will allow more intelligent interpretation
- but it will also be reflected in a more expressive interface with external representation

Expert Users
Shared Control

@@ Line 17: / Line 17: @@
 #*supported by poor communication channels (screen, keyboard, mouse)
 ====Human Interface Design Principles====
-#*based on fundamental principles of human-computer interaction
+*based on fundamental principles of human-computer interaction
-#*how do these principles limit the computer-human interface?
+*how do these principles limit the computer-human interface?
-#Metaphors with familiar noncomputer world
+#Metaphors from familiar noncomputer world
 #*computer files represented as documents in paper folders placed on desktop
 #*files deleted by dragging them to the trash can
 #*trying to overcome the limitations of the desktop metaphor (rooms, buildings, village)
 #*automobiles have developed their own interfaces without metaphors based on horses
-#Three classic Problems with Metaphors
+#Problems with Metaphors
 #*target domain has features not in the source domain (e.g. replace command in text editor)
 #*source domain has features not in the target domain (e.g. marking of typewriters)
 #*some features exist in both domains but work differently (e.g. white space as character)
 #Trash Can Metaphor
+#*single-trash-can metaphor has led to asystem that fails to meet user's needs
+#*to avoid the confusion of multiple trash cans in the interface, all trash cans are combined
+#*when user empties the trash to create room on a floppy disk, both trashe cans are deleted
+#*this is a limitation that does not serve the user's real needs
+#Desktop Metaphor
+#*save training time by taking advantage of having learned to operate a traditional office
+#*next generation of users will make their learning investments with computers
+#Direct Manipulation
+#*users interact directly with objects in the interface (e.g. drag and drop a document)
+#*user cannot group a related series of basic actions into one high-level action
+#See-and-Point
+#*users interact with computer by pointing at the objects they see on the screen
+#*we have lost all power of language, and cannot talk about objects that are not visible (yet)
+#*utilize more of the power of language to communicate more prececly
+#Consistency
+#*difficult to aply in real situation with wide array of conflicting things
+#*learning will be reduced if objects with similar function always look / behave alike
+#*in real life we have a wide range of appearances and they can still be easily recognizable
+#WYSIWYG
+#*what you see is what you get > document on the screen will look the same when printed
+#*problem that it is usually equivalent to WYSIATI (what you see is all there is)
+#*WYSIWYG document only shows final printed representation, not the user's intentions
+#*Standard Generalized Markup Language (SGML) preserves semantic meaning
+#*might be useful to have a different representation whe npreparing the document
+#*electronic information should be modularized and enabled to link to backup information
+#User Control
+#*many situations where we do not want to be in control > delegate to machines
+#*even if control is desirable, full control is becoming impossible with networked computers
+#Feedbakc and Dialog
+#*computer interface should provide the user with clear and immediate feedback on actions
+#*delegation of sequence of activities to an agent or encapsulated in a script
+#*then tehre is no longer a need for detailed and continuous feedback
+#Forgiveness
+#*user actions should generally be reversible and users should be warned of data loss
+#*computer needs to build a deeper model of our intentions and history
+#Perceived Stability
+#*elements in the computer interface should not be changed without user's involvement
+#*but deviding control between the user and the computer or networked computers
+#*stability can be boring
+#Aesthetic Integrity
+#*graphic design of the interface should be simple, clean, and consistent
+#*if compters could communicate with richer langugage, look would be less important
+#*richness can increase usability by making it easier to distinguish
+#Modelessness
+#*computer interface should not have distinct modes that restrict the user's actions
+#*users should be able to perform any task at any time
+#*problem of modelessness > user cannot cope with everything at once
+====Anti-Mac Interface====
+#Central Role of Language
+#*language lets us refer to things not immediately present, potential actions
+#*encapsulate complex groups of objects or actions and refer to them with single name
+#*ability to deal with imprecise language will increase the computer's flexibility
+#*command line interfaces have some of the advantages of language
+#*command line interfaces have rich syntactic structure to form complex commands
+#*but only a limited number of commands and cannot tolerate synonyms, misspellings
+#Richer Internal Representation of Objects
+#*current interfaces have acces to very little information about the used objects
+#*the only information about a file may be its name, size, and modification date,
+#*the type of data it contains, and the application that created it
+#*but it could include its authors, topic matter, keyword, importance, relations
+#More Expressive Interface
+#*richer internal representation of objects will allow more intelligent interpretation
+#*but it will also be reflected in a more expressive interface with external representation
+#Expert Users
+#Shared Control