USABILITY
What is Usability?

   Usability is the measure of the quality
    of a user's experience when
    interacting with a product or system —
    whether a Web site, a software
    application, mobile technology, or any
    user-operated device.
What is Usability?
 Usability is a combination of factors
 that affect the user's experience with
 the product or system, including:
 ◦ Ease of learning
 ◦ Efficiency of use
 ◦ Memorability
 ◦ Error frequency and severity
 ◦ Subjective satisfaction
Why is usability important?
   Low usability results in:
    ◦   Frustrated users
    ◦   Visitors leaving
    ◦   Reduction in repeat visits
    ◦   Higher support costs
    ◦   Decreased productivity
Process Of Flow Of Usability
What is Usability Testing?

 ◦   A way to evaluate the interface with
     real users.

 ◦   Can be done in a lab or in their
     environment.

 ◦   Can be performed on paper prototypes
     as well as implemented systems.
Types of Usability Problems
 Product doesn‟t match job or task
 Poor organization/layout
 Unexpected occurrence of events
 Product not self-evident
 Requires recall rather than recognition
 Inconsistent screens, messages,
  terminology
Types of Usability Problems
 Design is inefficient
 Cluttered or unattractive design
 No feedback or poor feedback about
  status or errors
 No exit or undo
 Help or documentation is not helpful
Usability Attributes
 Attributes should be measurable
 Example Attributes include
    ◦   Time to complete a task
    ◦   % of task completed
    ◦   Number or % of errors made
    ◦   % of users who like the design
    ◦   No of times user asks for help/gets lost
Planning
 ◦   Define the purpose of the Web site
 ◦   Identify target users
 ◦   Get to know your users
 ◦   Define the users‟ tasks
 ◦   Determine scope, usage and change
     characteristics of the information
 ◦   Define the “personality” of your site
 ◦   Put together your Web site team
Usability Considerations

 Usability includes considerations such
  as:
 Who are the users, what do they
  know, what can they learn?
 What do users want or need to do?
 What is the users' general
  background?
 What is the users' context for
  working?
 What must be left to the machine?
Other Considerations

 Can users easily accomplish intended
  tasks at their desired speed?
 How much training do users need?
 What documentation or other
  supporting materials are available to
  help the user?
 Can users find solutions in these
  materials?
Other Considerations
 What and how many errors do users
  make when they interact with the
  product?
 Can the user recover from errors?
 What do users have to do to recover
  from errors?
Other Considerations
 Does the product help users recover
  from errors? For example, does software
  present comprehensible, informative,
  non-threatening error messages?
 Does the product meet the special needs
  of disabled users? (Is it accessible?)
 Are there substantial differences
  between the cognitive approaches of
  various users that affect the design, or
  does a one-size-fits-all approach work?
Usability Checklist
   Can visitors read the text, or is a
    background color or texture interfering
    with the readability?

   Does the layout of the screen
    encourage visitors to move their eye
    focus in a logical, orderly fashion, or
    are visitors visually lost?
Usability Checklist
   Is the site designed with a particular
    target audience in mind, or is it trying to
    be all things to all people (and therefore
    nothing to nobody)?

   Does the order visitors move through a
    page, or set of pages, match the way
    they want to do their work, or do visitors
    get lost trying to find information or fill out
    a form?
Usability Checklist
   Do you know the purpose of the site,
    or has the site grown appendages that
    don't hang together?

   Have you chosen the best content
    type (text, graphics, audio...) for the
    material and the hardware and
    software environment of your target
    audience, or is your content presented
    inappropriately?
Usability Checklist
   Images & animations: Use the alt
    attribute to describe the function of
    each visual.

   Image maps: Use the client-side map
    and text for hotspots.

   Multimedia: Provide captioning and
    transcripts of audio, and descriptions
    of video.
Usability Checklist
   Hypertext links: Use text that makes
    sense when read out of context. For
    example, avoid "click here."

   Page organization: Use headings,
    lists, and consistent structure. Use
    CSS for layout and style where
    possible.

   Graphs & charts: Summarize or use
    the longdesc attribute.
Usability Checklist
   Scripts, applets, & plug-ins - Provide
    alternative content in case active
    features are inaccessible or
    unsupported.

   Frames - Use the noframes element
    and meaningful titles.

   Tables - Make line-by-line reading
    sensible. Summarize.
Links
   Use Consistent Clickability
    ◦ Colored text (blue)
    ◦ Underlined text
    ◦ Graphic + text

   Write meaningful labels
    ◦ Users should be able to sense the link‟s destination
      from its label.
    ◦ Link labels should match the names of their
      destination pages.
    ◦ Link labels should be clearly different from each
      other.
    ◦ Links embedded in text should be highly descriptive
      (9-10 words) and make sense when read out of
      context. Users ignore surrounding text.
Scrolling
   Eliminate horizontal scrolling

   Avoid scroll stoppers

   Use appropriate page lengths:
    ◦ Short pages for „homepage‟, navigation,
      scanning
    ◦ Longer pages for reading continuous content
    ◦ Stay within 4 screenfuls

   Use a clickable list of contents on long
    pages
Images
   Use images that add value

   Use thumbnails to preview large
    images

   Place large images „below the fold‟

   Label images to help users
    understand them.
Summary
   Have a goal or purpose for your site.

   Spend time in planning and design.

   Don‟t do things because you can, do
    them because they add value.

   Continually evaluate and update your
    site.
Conclusion
 ◦ Plan to apply at least one of these
   techniques to your current and/or next
   project.

 ◦ Identifying users and their tasks is most
   important

Usability

  • 1.
  • 2.
    What is Usability?  Usability is the measure of the quality of a user's experience when interacting with a product or system — whether a Web site, a software application, mobile technology, or any user-operated device.
  • 3.
    What is Usability? Usability is a combination of factors that affect the user's experience with the product or system, including: ◦ Ease of learning ◦ Efficiency of use ◦ Memorability ◦ Error frequency and severity ◦ Subjective satisfaction
  • 4.
    Why is usabilityimportant?  Low usability results in: ◦ Frustrated users ◦ Visitors leaving ◦ Reduction in repeat visits ◦ Higher support costs ◦ Decreased productivity
  • 5.
    Process Of FlowOf Usability
  • 6.
    What is UsabilityTesting? ◦ A way to evaluate the interface with real users. ◦ Can be done in a lab or in their environment. ◦ Can be performed on paper prototypes as well as implemented systems.
  • 7.
    Types of UsabilityProblems  Product doesn‟t match job or task  Poor organization/layout  Unexpected occurrence of events  Product not self-evident  Requires recall rather than recognition  Inconsistent screens, messages, terminology
  • 8.
    Types of UsabilityProblems  Design is inefficient  Cluttered or unattractive design  No feedback or poor feedback about status or errors  No exit or undo  Help or documentation is not helpful
  • 9.
    Usability Attributes  Attributesshould be measurable  Example Attributes include ◦ Time to complete a task ◦ % of task completed ◦ Number or % of errors made ◦ % of users who like the design ◦ No of times user asks for help/gets lost
  • 10.
    Planning ◦ Define the purpose of the Web site ◦ Identify target users ◦ Get to know your users ◦ Define the users‟ tasks ◦ Determine scope, usage and change characteristics of the information ◦ Define the “personality” of your site ◦ Put together your Web site team
  • 11.
    Usability Considerations  Usabilityincludes considerations such as:  Who are the users, what do they know, what can they learn?  What do users want or need to do?  What is the users' general background?  What is the users' context for working?  What must be left to the machine?
  • 12.
    Other Considerations  Canusers easily accomplish intended tasks at their desired speed?  How much training do users need?  What documentation or other supporting materials are available to help the user?  Can users find solutions in these materials?
  • 13.
    Other Considerations  Whatand how many errors do users make when they interact with the product?  Can the user recover from errors?  What do users have to do to recover from errors?
  • 14.
    Other Considerations  Doesthe product help users recover from errors? For example, does software present comprehensible, informative, non-threatening error messages?  Does the product meet the special needs of disabled users? (Is it accessible?)  Are there substantial differences between the cognitive approaches of various users that affect the design, or does a one-size-fits-all approach work?
  • 15.
    Usability Checklist  Can visitors read the text, or is a background color or texture interfering with the readability?  Does the layout of the screen encourage visitors to move their eye focus in a logical, orderly fashion, or are visitors visually lost?
  • 16.
    Usability Checklist  Is the site designed with a particular target audience in mind, or is it trying to be all things to all people (and therefore nothing to nobody)?  Does the order visitors move through a page, or set of pages, match the way they want to do their work, or do visitors get lost trying to find information or fill out a form?
  • 17.
    Usability Checklist  Do you know the purpose of the site, or has the site grown appendages that don't hang together?  Have you chosen the best content type (text, graphics, audio...) for the material and the hardware and software environment of your target audience, or is your content presented inappropriately?
  • 18.
    Usability Checklist  Images & animations: Use the alt attribute to describe the function of each visual.  Image maps: Use the client-side map and text for hotspots.  Multimedia: Provide captioning and transcripts of audio, and descriptions of video.
  • 19.
    Usability Checklist  Hypertext links: Use text that makes sense when read out of context. For example, avoid "click here."  Page organization: Use headings, lists, and consistent structure. Use CSS for layout and style where possible.  Graphs & charts: Summarize or use the longdesc attribute.
  • 20.
    Usability Checklist  Scripts, applets, & plug-ins - Provide alternative content in case active features are inaccessible or unsupported.  Frames - Use the noframes element and meaningful titles.  Tables - Make line-by-line reading sensible. Summarize.
  • 21.
    Links  Use Consistent Clickability ◦ Colored text (blue) ◦ Underlined text ◦ Graphic + text  Write meaningful labels ◦ Users should be able to sense the link‟s destination from its label. ◦ Link labels should match the names of their destination pages. ◦ Link labels should be clearly different from each other. ◦ Links embedded in text should be highly descriptive (9-10 words) and make sense when read out of context. Users ignore surrounding text.
  • 22.
    Scrolling  Eliminate horizontal scrolling  Avoid scroll stoppers  Use appropriate page lengths: ◦ Short pages for „homepage‟, navigation, scanning ◦ Longer pages for reading continuous content ◦ Stay within 4 screenfuls  Use a clickable list of contents on long pages
  • 23.
    Images  Use images that add value  Use thumbnails to preview large images  Place large images „below the fold‟  Label images to help users understand them.
  • 24.
    Summary  Have a goal or purpose for your site.  Spend time in planning and design.  Don‟t do things because you can, do them because they add value.  Continually evaluate and update your site.
  • 25.
    Conclusion ◦ Planto apply at least one of these techniques to your current and/or next project. ◦ Identifying users and their tasks is most important