1. CSE 8316
User
Interface
Design
Rob Oshana
Southern
Methodist
University

2. Interaction Styles

3. Agenda Windows Files Storage and Retrieval Systems Menus Forms
Dialog boxes
Typed command languages

4. Introduction
Interaction Style: A collection of interface objects and associated techniques from which the designer chooses
Provide behavioral view for user communication
These objects are implemented with widgets/toolkits
This implementation falls in the constructional domain

5. Steps to good GUI design
Know your client
Understand the business function
Understand the principles of good screen design
Develop system menus and navigation schemes
Select the proper kinds of windows

6. Steps to good GUI design
6. Select the proper device based controls
7. Choose the proper screen based controls
8. Write clear text and messages
9. Provide effective feedback and guidance and assistance

7. Steps to good GUI design
10. Provide effective internationalization and accessibility
11. Create meaningful graphics, icons, and images
12. Choose proper colors
13. Organize and layout windows and pages
14. Test, test, and retest

8. Windows

9. History Xerox PARC - Apple Mac Contributed many things mouse
rectangular window
scrollbar
push button
desktop metaphor
pull down menus

10. PARCs Principles Modes Overlapping Windows Tiling
confusing and frustrating
Overlapping Windows
metaphor of overlapping sheets on desk
Tiling
more than one application on the screen

11. Description
Window: Screen object that provides basis for other interaction objects
All interaction occurs through the window
Two types:
Primary: The first window for an application, acts as ``parent'' for other windows
Secondary: Created from primary. Include such objects as dialogue boxes

12. Standard window decorations
Control menu
Maximize button
Window border
button
Title bar
Minimize button
Window Name
Client area
Window border
Minimize button
Close button
Title bar
Maximize button
Window Name
Client Area
Sizing grip

13. Interaction restrictions in modeless and modal windows

14. Unnecessary Rooms
Should not add windows to our program unless they have a special purpose that can’t or shouldn’t be served by existing windows
A dialog box is another room. Have a reason to go there
Build function controls into the window where they are used

15. Necessary Rooms
When providing a function out of the normal sequence of events, provide a special place to perform it
Examine the users goals
Don’t put every function in a dialog box

16. Windows Pollution A gallon of oil won’t make a bicycle pedal itself
No way to show the connections between lots of windows
modal dialogs don’t count; they always get you back immediately to the point of departure
Tools make it easy to make lots of windows and boxes

17. Guidelines Don't overuse windows
Minimize window manipulation needed
Give user flexibility to move and resize
Tiled windows give better user performance, but require more area
Appearance and behavior of primary window should be consistent
Primary is user's home base

18. Guidelines Use different windows for different independent tasks
Allows one-to-one mapping to be set up in mental model
Completion of task equates to completing window

19. Guidelines
Use different windows for different coordinated views of the same task
Permits examination from different perspective or detail
All views should be updated uniformly to prevent inconsistency between windows

20. Files

21. Tragedy of the file system
Most difficult to understand
Main memory and disk storage confusing
Programs stored in two places at once
Putting might on will; user might say no but will probably say yes

22. Problems caused by disks
Disks and files make users crazy
Influence of the file system on the user interface is deep
We still render the implementation model to the user

23. Problems caused by disks
Behavior characteristics applied based on real world metaphor
only one document
it belongs to the user
Implementation model violates most of these
Disk drive is the book shelf
Main memory represents the hands doing the editing (copy is made!)

24. Dispensing with the disk model
“Put the book back on the shelf” instead of “Save changes”
Structure commands according to the goals of the user instead of according to the needs of the operating system
Change “file” to “document”

25. Designing software with the proper model
Treat documents as single instances instead of copies - unified file model
Save automatically at intervals
countdown clock
noticeable delay
wait til the user stops typing to save

26. Designing software with the proper model
Closing
Does not map well to unified model
Required knowledge of file system

27. Designing software with the proper model
Rude error message for something that a user should be able to do

28. Archiving
No explicit function for making a copy of or archiving a file
Must use the “save as” function
Not very clear
“Save as” dialog is the wrong tool for making and managing copies

29. Unify the file model
If the file system is going to show the user a file that cannot be changes because it is already in use, this should be indicated to the user
special color or icon
Pull a hammer out of the toolbox only to look inside and find another hammer!!

30. Document Management Goal directed functions
creating a copy of the document
creating a milestone copy of the document
naming and renaming the document
placing and repositioning the document
specifying a stored format for the document
reversing some changes
abandoning all changes

31. How did we get here?
From a user’s point of view, there is no reason for a disk to exist
Advantages for the engineer;
disks are cheaper than solid state memory
once written to, disks don’t forget when the power is off
disks provide a physical means of moving information from one computer to another

32. How did we get here? Drawbacks Mainly a cost issue
slower than solid state memory
less reliable with many moving parts
more space and power
CPU needs help to access
processing more complex
Mainly a cost issue

33. Storage and Retrieval Systems

34. Storage vs. Finding
In the real world, storing and retrieving are linked
Not so in the digital world
Storage system; a tool for placing goods into a repository for safekeeping
physical container
tools necessary to put objects in and take them back out again

35. Storage vs. Finding
Retrieval system; method for finding goods in a repository
logical system that allows the goods to be located according to some abstract value
name
position
aspect of contents

36. Storage vs. Finding Real world retrieval indices
author
subject
title
We ignore these in the computer world
where we put them
what we named them

37. Storage vs. Finding Books can also be identified by
color
shape
Location may change
bookshelf
coffee table
night stand
We don’t find a book by referring to its contents!!

38. Retrieval Methods Positional retrieval; remembering where you left it
Identity retrieval; remembering its identifying name
Associative retrieval; remembering some inherent quality of the document

39. Indexing
Libraries used Dewey Decimal system because names can be too disparate or insufficiently unique
good approach to storage
Card catalog helps in retrieval
Libraries provide three indices
author
subject
title

40. Indexing Each index is associative
allows the user to find the book according to an inherent property of the book other than its identifying number or its location on the shelf
Retrieval is done by looking up one of the indices, find its number, find the row of books, examine signs

41. Retrieval Systems in Computer

42. Retrieval Systems in Computer

43. An associative retrieval system
Enables us to find documents by their contents
Should know where documents can be found
Create temporary or permanent groups of files
Browse by synonym or related topic
Assign attributes to files

44. Things to remember The program that created the file
The type of document
The program that last opened the document
If the document is very large or small
If the document has been untouched for a long time
The length of time the document was last open

45. Getting Better
SGML and XML
OLE
Unix standard file formats

46. Menus

47. Brief History
Typing commands into a standard keyboard was once considered revolutionary
Command line interface
Hard to know what to type
Still preferred today in some spaces
Modern complexity makes it hard to use

48. Brief History Hierarchical menu in the late 70’s
User could forget many of the commands and option details
Read information of the screen instead of keeping it in your head
Very sequential in nature due to batch nature of computers at the time

49. Example Enter transactions Close books for month
Print income statement
Print balance sheet
Exit

50. 1. Enter Transactions Enter Invoices Enter payments
Enter invoice corrections
Enter payment corrections
Exit

51. Lotus 1-2-3 Revolutionary Visible hierarchical menu
Took advantage of 1979 computer screens
2000 characters/screen
25 horizontal rows
80 characters each
Powerful because it enabled users to move in an ad hoc, piecemeal fashion, from beginner to expert

52. Monocline grouping
Method of organizing things into a single layer of groups
simple and powerful (users mental model)
the method we use at home/office
never exceeds a single level of nesting
Most users don’t like hierarchies
in a file cabinet you don’t see folders within folders

53. Command types
Command vector; each distinct technique for issuing instructions to a program
Multiple command vectors - each function has
menu commands
toolbar commands
keyboard commands
direct manipulation commands

54. Migrating commands Immediate vectors
direct manipulation; immediate affect on the information without intermediary
menus and dialog boxes don’t have this
toolbar-button command vectors
no delay between pressing a button and seeing the results of the function
Most frequently used commands migrate to buttons on the toolbar

55. Menu commands
Menu commands that have the advantage of natural language descriptions of the functions, and the detailed controls and data that appear on corresponding dialog boxes
Menus and dialog boxes are the pedagogic vector

56. Menus Hard to first understand what a complex application can do
We look at the menu
Similar to a restaurant menu that we view at the entrance to get a feel for type, price, setting, etc

57. Menus must be complete
Full selection of actions and facilities available in the program
Hints that describe keyboard equivalents

58. Example

59. Description
Menu: Object that provides a list of items from which one or more of the items are selected.
One of the most popular, easiest to use interaction objects
Promotes recognition over recall
Reduces typing errors
Wide assortment of styles

60. Structures of menus Single menus Sequential menus Simultaneous menus
Hierarchical menus
Connected menus

61. Single menus
Single screen to seek input or request action to be performed
Conceptually require choices from one menu only and no others will follow
User only considers immediate consequences
May be iterative – data entry

62. Single menus
Galitz, Essential Guide to
User Interface Design

63. Sequential linear menus
Presented in a series of screens possessing only one path
Presented in preset order (may be problem if user wants a different order)
Objective to specify parameters or for entering data
Path may be short or long (long may become tedious)
All important and require user action

64. Sequential linear menu
Galitz, Essential Guide to
User Interface Design

65. Sequential linear menu

66. Simultaneous menus
Instead of being presented on separate screens, all menu options are available simultaneously
Menu may be completed in order desired by user
Choices can be skipped and returned to later
Tedium associated with long series of sequential menus greatly reduced
Large collections of alternatives can clutter screen – paging or scrolling may be necessary
Important to clearly indicate menu choice relationships and dependencies (this can be confusing if not done right)

67. Simultaneous menus
Galitz, Essential Guide to
User Interface Design

68. Hierarchical Menus
When many relationships exist between menu alternatives, and some menu options are only appropriate depending on a previous selection, a hierarchical structure is the best solution
This approach provides an increasing refinement of choice as menus are stepped through
Options to suboptions
Categories to subcategories
Pages to sections to subsections
Represent with an inverse tree

69. Hierarchical Menu
Galitz, Essential Guide to
User Interface Design

70. Hierarchical Menus Examples are menu bars with pull-downs
Web sites with navigation links
Order and structure of branching in a hierarchy is preset
Normal order of flow is one way top down
Branching order may not fit user conception of the task flow
May go down wrong paths

71. Connected menus Networks of menus interconnected in some manner
Movement not restricted to a hierarchical tree – permitted between most or all menus in the network
My be cyclical or acyclical (movement in only one direction)
Gives user full control over navigation flow
For novice, complexity and navigation may be daunting

72. Connected menu
Galitz, Essential Guide to
User Interface Design

73. Event trapping menus
Provide ever-present background of control over the system’s state and parameters while the user is working on a foreground task
Serve three functions
Immediately change some parameter in the current environment (bold text)
Take user out of current environment to perform function (spell check)
Exit and allow user to go to new environment (exit)

74. Event trapping menus Paste option will only function if there is
something in a clipboard to paste

75. Suggested Menu Structure
Program Document Pieces Help
Properties
Views
Functions
Access
Properties
Views
Functions
Access
Properties
Views
Functions
Access

76. Suggested Menu Structure
Far left is the topic of broadest scope (program)
Move to the right with diminishing scope
Submenus in descending order of importance
properties
views of them
functions that operate on them
access to the “outside world”

77. Program Menus Default settings What templates are available
What mode it is in
Configuration of standard interface idioms like toolbars
Personalization items like color and graphics

78. Document menus Covers document under construction
Prime menu items cover properties of the currently active document
Views (draft vs presentation)
Functions that operate on the entire document at once
calculating spreadsheets
formatting text
Most recently used information

79. Pieces of the document
Covers objects embedded in the document (tables or images)
Only active when the particular object is selected
Handles transformations like rotation, formatting
Ability to load and save objects to/from other documents/disk

80. File Menu
accelerators
mnemonics
separator
MRU list

81. Pop up menu
Used to present alternatives or choices within the context of the task
Choices are context sensitive depending on where the pointer is positioned and when the request is made

82. Pop up menu Advantages Appear in working area
Do not use window space when not displayed
No pointer movement needed if selected by button
Vertical orientation efficient for scanning and grouping
Disadvantages
Existence must be learned and remembered
Require a special action to see the menu
Items are smaller than full size buttons which slows selection time
Display locations may not be consistent

83. Pop up menu guidelines
Provide a pop-up menu for common, frequent, contextual tasks
Items that cannot be chosen due to the current state of an application should not be displayed
Continue to display pop-up until
Choice is selected
An action outside the pop-up is initiated
The user removes the pop-up

84. Iconic menu

85. Iconic menu
Use to remind users of the functions, commands, attributes, or application choices available
Create icons that
Help enhance recognition and hasten option selection
Are concrete and meaningful
Clearly represent choices

86. Iconic menu advantages/disadvantages
Pictures help facilitate memory of applications
Large size increases speed of selection
Pictures consume more screen space and difficult to organize for scanning efficiently
Creating meaningful icons requires special skills and extended time

87. Menu System Standard menus Optional menus File menu Edit menu
Windows menu
Help menu
Optional menus
View menu
Insert menu
Setting menu
Format menu
Tools menu

88. Types Push-Button Menus
Choices are in terms of push-buttons, sometimes called a button bank
Typically one of the selections is the default and is highlighted in some way
Selection may be based on pointer object or keyboard accelerators
Articulatory feedback is given
Need to label carefully and clearly -- shortness of label versus clarity of meaning

89. with text labels, graphic labels,
Example push buttons
with text labels, graphic labels,
or both

90. Types Radio-Button Menus Check-Button Menus
Choices are exhaustive and mutually exclusive, selecting one deselects another
Selection indicated by highlighted box
Typical for dialogue or property boxes
Check-Button Menus
Like a radio-button menu, but more than one item may be selected
Selections indicated by highlighted box, check mark, etc

91. Examples of menu options
in Motif

92. Example radio button
in MS Windows

93. Example check box group
in Motif

94. Example of unavailable
menu option in Motif

95. Types
Pull-Down Menu
Menu title is shown. When selected, entire menu appears, selection is made and menu is hidden
Since only title is permanent, provides compromise between pop-up and continuously displayed menus
Selection may be done with one or more user actions

96. Example pull-down menu
in MS Windows

97. Types Pop-Up Menus Menu appears at location where mouse is pressed
Unlike pull-down, there is no evidence the menu exists
Contents may change depending on location of cursor
Minimizes mouse movement and screen real-estate

98. Example pop-up menu in Motif

99. Types Option Menu Toggle Menu
Appears much like a field in a form, but when selected a menu appears
Distinct from pop-up since visual cue of existence
Toggle Menu
One choice is shown.
Clicking on item will sequence through all possible choices
User is not presented with all choices at once

100. Example option menu in Motif

101. Example menu button in Motif

102. Types
Cascading Menus
Like a pull-down, however selecting one choice brings up another menu
Helps group into hierarchical fashion
Visual clue to existence should be provided
Requires more coordination than other styles

103. Organization of options in submenus

104. Types Pie Menus Choices arranged as wedges in circle
Minimizes mouse movement over linear list
Other aspects (such as radius or wedge size) can be used

105. Types Palette/Iconic Menus
Menu consists of an array of icon push-buttons.
Used for frequently chosen features or in graphically oriented applications
Choice is indicated by highlighting icon

106. Types Embedded Menus Dynamic Menus
Menu items are highlighted/underlined text
Selecting text performs action
Also called hypertext
Dynamic Menus
Menu contents change over time
Sometimes done by graying out selection items

107. Example submenu in Motif

108. Example tear-off menu
in Motif

109. Example menu window
in Motif

110. Guidelines
Use the user tasks and system functions to organize hierarchical menus
Goal is three to four levels with four to eight items per level
Can place tasks on paper and organize into hierarchy to aid design
Use meaningful groupings of menu choices

111. Guidelines Use meaningful ordering of menu choices
Orderings include alphabetical, numerical or temporal, frequency
Not good to dynamically change ordering

112. Guidelines Use brief descriptions for menu choices
Single word is best
Otherwise begin each choice with same type of word (noun, verb, etc)
Use a consistent layout across all menus and keep the screen uncluttered
Should be covered in customized style guide

113. Guidelines Allow Shortcuts
Separate with white space, use consistent help messages
Allow Shortcuts
Provide accelerator keys and macros

114. Other Design Tips Disable menu items when they are moot
Parallel visual symbols on parallel command vectors
Don’t use bang menu items

115. Parallel visual symbols

116. Tips for Creating Good Accelerators
Follow standards
Provide for their daily use
Show how to access them

117. Forms

118. Description
A series of labeled fields that are to be filled in by the user
Intuitive interface, however free form typing is more prone to errors
Various types of fields for forms

119. Field Types User-Typed Strings User Choices from a List
Can have validated and invalidated
Validated fields should have some visual cue
User Choices from a List
Toggle and option menus are good for this situation
Default Values for Fields
All fields for which values can be predefined should have them

120. Types of Fields Required vs. Optional Values Dependent Fields
Should have visual cue as to which is optional and which required
Dependent Fields
These are fields that are required if a particular value is entered in another field.

121. Guidelines Use a consistent, visually appealing layout and content
Group fields and separate with white space
Provide titles and concise instructions
Be consistent across different forms

122. Guidelines
Do not assume that existing paper forms convert directly to screen designs and a good user interface
Paper forms frequently are not optimal
Good opportunity to evaluate purpose of forms, involving users
Screen size versus paper is different.
Attempting to copy the form directly, but changing some aspects can be confusing

123. Guidelines Use appropriate visual cues for fields on forms
Indicate maximum length, types of input allowed, etc.
Use familiar and consistent field labels and abbreviations
Field labels should be concise, using standard terms
Labels should be located to the left of the field with a simple delimiter

124. Guidelines Use logical navigation among fields
Arrow keys, return key, tab
Permit wraparound or direct access using mouse
Use logical navigation within fields
Support editing and error correction of fields
Do no require entire field be replaced, but rather permit changing of single characters

125. Guidelines
Use consistent, informative error messages for unacceptable characters and values
Provide explanatory messages for expected field inputs
Can be made available on user demand or automatically provided.
If automatic, should be concise

126. Guidelines Provide default values in fields whenever possible
Fill in obvious fields, allow user to change
Can help describe format for input
Provide a completion indicator for each form-filling screen
Give user control over when finished
Permit cancellation and ability to return to partially completed form

127. Dialog Boxes

128. Description
A rectangular, delineated screen area that is used for messages, text entry, commands, selection and user control
May be initiated by user or system
Temporary object that obscures part of screen

129. Suspension of Normal Interaction
Dialog boxes are superimposed over the main window of the owning program
Engages user by offering information and requesting some input
After editing user has option of accepting or rejecting changes
Dialog box then disappears

130. Suspension of Normal Interaction
When the application presents a dialog box, it is temporarily moving the action out of the mainstream
Taking the focus off the dinner party and into the kitchen for preparation of the food
May be crucial but not the main point
Should be use for secondary interaction

131. Put primary action on the primary window
Dialogs break flow

132. Dialogs break flow
Appropriate for functions or actions out of the mainstream interaction
Good for presenting infrequently used functions and settings
Well suited for concentrating information related to a single subject
Serve two masters; frequent users and infrequent user

133. Dialog box basics All dialog boxes have an owner
Always placed visually on top of the owning program
Every dialog box has at least one terminating command OK
Cancel

134. Modal Dialog boxes Most common
Once the box comes up, the owning program cannot continue until the dialog box is closed
It stops the proceedings
User can activate other programs while the modal dialog box is up
dialog box remains indefinately

135. Modal Dialog boxes Easiest for users and designers to understand
“Stop what you are doing and deal with me now! When you are done you can return to what you were doing”
Like a subroutine call
Rigidly defined behavior

136. Modal Dialog boxes
Function-oriented; operates on the entire program or document
Process- or property- oriented; operates on the current selection
Application modal; can only stop their owning application
System modal; brings every program in the system to a halt (catastrophic conditions only!)

137. Modeless Dialog boxes Less common and more misunderstood
Owning program continues to run without interruption
Does not stop the proceedings
Have terminating commands
Scope of operation is often unclear

138. Modal Dialog box design tips
Visually differentiate modeless dialogs from modal dialogs
Give modeless dialog boxes consistent terminating commands
Never change the terminating button captions
Things that behave differently should look different!

139. Making modeless dialog boxes into toolbars

140. Typical state-of-the-art modeless dialog box

141. Property Dialog Box
Usually modal, but not uncommon to find these modeless

142. Function Dialog Box Usually summoned from the menu
Most frequently modal dialog boxes
Control a single function
printing
inserting
spell check

143. Bulletin Dialog Box Most abused part of the interface
Error message box
Property and function dialog boxes are intentionally requested by the user
they serve the user
Bulletins are issued unilaterally by the program
they serve the program

144. Bulletin Dialog Box

145. Process Dialog Box
Like bulletin in the sense that they are erected at the program’s discretion rather than users request
Indicate that the program is busy with some internal function
Alerts the user to the program’s inability to respond normally
Warns the user not to be overcome with impatience

146. Process Dialog Box Single CPU systems require this to some extent
good at time sharing between software tasks
once the hardware becomes involved problems arise
accessing the disk
dialing up a modem

147. Process Dialog Box

148. Process Dialog Boxes
The program must inform the user when it gets stupid
Four basic tasks
make clear to the user that a time-consuming process is happening
make clear to the user that things are completely normal
make clear to the user how much more time the process will take
provide a way for the user to cancel the operation

149. Process Dialog Boxes
Process meter

150. Types List Boxes Entry Boxes Scrollable sequence of users choices
Contents are usually dynamic
Frequently search cability exists
Entry Boxes
Allows user to enter data
May be one line (as in form field) or multi-line
Supports full editing

151. Example list box in Motif

152. Example list and text box
used in an incremental
search in Motif

153. Example drop-down
list box in Motif

154. Example combo box in Motif

155. Example drop-down combo
box in MS Windows

156. Example spin box in Motif

157. Types Message Boxes Usually created by system (not at user request)
Contains information from user and allows limited interaction

158. Types
Dialogue Boxes
Composite interaction object that contains other interaction objects.
Typically part of user task sequence
Group various, related functions
Modal dialogues grab the user focus and require the user to resolve before continuing
Modeless allows user to interact with other window without finishing it

159. Example text box and label
in MS Windows

160. Example text box labels
providing format cues

161. Guidelines Use brief but comprehensible instructions
Because of potential complexity of boxes, instructions should be provided
Use carefully worded messages
Use logical groupings and orderings of objects in a box
Use visual cues to delineate groupings within boxes
Keep layout consistent and visually appealing

162. Guidelines Make defaults visually distinctive
Menu selections that lead to dialogue boxes should contain a visual cue
Boxes should disappear under user control
Windows that appear and disappear ``magically'' confuse the user
Exception is for boxes displaying status information

163. Components of a scroll bar
in MS Windows

164. Example sash in Motif

165. Example tabbed pages
in MS Windows

166. Example scale in Motif

167. Example gauge in Motif

168. Dialog Box Etiquette

169. Design Tips All dialog boxes should have caption bars
Use verbs in function dialog caption bars
Use object names in property dialog caption bars
Dialog boxes should be as small as possible but no smaller

170. Reduce Excise

171. Terminating Commands for Modal Dialog Boxes
Offer OK and CANCEL buttons on all modal dialog boxes
CANCEL good for pedagogical purposes
Bulletin dialog boxes (errors) can get away with just an OK
Process dialogs need a CANCEL to stop a time consuming process
Never user terminating words in dialog boxes (CLOSE)

172. The Close Box Don’t put close boxes on modal dialogs
disposition of changes is unclear
changes accepted or rejected?

173. Tabbed Dialog Sometimes called “multi-pane” dialog Panes and tabs
Helps with size and complexity
Follows the users mental model for how things are stored
monocline grouping (one level deep)
Content must have meaningful rational

174. Put terminating buttons in un-tabbed area
Tabbed Dialogs
Tabbed area
Un-tabbed area
Put terminating buttons in un-tabbed area

175. Extreme Case of Tabbed Dialogs
All idioms have
practical limits
Don’t stack tabs

176. Directed Dialogs
Changes and adapts its suite of gizmos based on some user input
Programming these can get complicated
May be confusing to the user
Effective when user is entering settings in a clearly sequenced manner

177. Directed Dialogs

178. Typed-Command Languages

179. Description Earliest form of communication
Can be very efficient to use, popular with frequent users
Requires extensive training and knowledge of syntax

180. Guidelines Use a consistent rule of formation for entering commands
Since learning is more difficult, consistency is essential
Typical formation is ``action-modifier(s)-object(s)''

181. Guidelines Choose meaningful, specific, distinctive command names
Can be very difficult since all commands are typically visible at once
May permit abbreviations, but that can cause additional confusion
Use diametrical opposites for commands that are logically opposite (e.g. create/destroy)

182. Guidelines Apply consistent rules for abbreviating commands
Single characters may work for small command sets
For larger, truncation appears best (over such techniques as dropping vowels, first and last letter, etc)
Allow easy correction of typing errors
Do not force user to retype lines that had errors, but allow editing.

183. Guidelines Allow frequent users to develop macros
Geared towards frequent users
Allows for increased speed and customization

184. Graphical Interfaces

185. Description
The term Graphical User Interface (GUI) has come to represent interaction objects such as windows, buttons, etc.
Generally use direct manipulation with an object-action paradigm and visual feedback
This is just a subset of various ways to use graphics to communicate. Call that superset graphical interfaces.

186. Types Data and Scientific Visualization Visual Databases
This includes charts, graphs, plots, etc.
Widely used in the scientific community to gain insight into large amounts of data (numbers)
Visual Databases
Store visual images much as you would store text
Use stored images to construct simulations

187. Types Animation Video Effective for simulating various scenarios
Also, like visualization, can show temporal relationships
Video
Combine audio/video with other windows
Requires more skill to design effectively

188. Types Multimedia and Hypermedia Virtual Reality
The integration of graphical, audio and video information with associative links
Links provide simple navigation through ``hyperspace''
Navigation must be designed carefully
Virtual Reality
Represents a greater immersion into the application with various sensory devices
Still very expensive with much still in development stage

189. Guidelines
Since many of these interaction styles are very new, there is little in the way of hard evidence. The following are heuristics based on common sense and experience
Use real-world analogies as much as possible
Since systems tend to model the real world, these analogies work best

190. Guidelines Keep the visual presentation as simple as possible
Avoid the tendency to do too much, just because you can

191. Guidelines Show different views of the same visual object
Use color sparingly and meaningfully
Use video sparingly
Only high-quality video should be used, and that is difficult to produce