accessibility zweb should be usable by everyone this includes users with: zvision impairments...

Accessibility

Web should be usable by everyone

This includes users with:Vision impairmentsHearing impairmentsMobility impairments

Statistics

8 million people with visual impairments

20 million deaf or hard-of hearing250,000 with spinal cord injuries500,000 with cerebral palsy330,000 with MSMore that half US population over 65

has some type of impairment

Issues involving Vision

Web very visually oriented Significant challengesSeverity ranges from total blindness

to low visionColor blindness Visual Stimuli

Information Delivery

Information display on traditional monitor not available to users with visual impairments

Two assistive technologies:Screen ReadersRefreshable Braille displays

Screen readers

Reads text component of web screenIncludes:LinksMenusDialog BoxesError Messages

Screen Readers

Several vendors offer screen readersPrices range from $300 to $1000Page must be reformatted to support

screen readersHTML “lang” attribute controls

language page will be read in

Refreshable Braille Display

For people who are deaf as well as blind screen readers do not work.

Translates text of page into BrailleSingle line of Braille textPrices range from $4500 to $14,500

Grade II Braille

Refreshable Braille Display

Reformatting Text

For screen readers to work text of page must be formatted to support linear delivery

Tabular dataLabel for ElementsSkip navigationAlt Tags for images

Tabular Data

Course Time Day Prerequisite Instructor

211 11:30 pm -1:00 pm MW None McDonald

211 10:30am - 12:00 pm TR None Luecking

212 5:45 pm - 9:00 pm M 211 Carter

212 11:30 pm - 1:00pm TR 211 Chan

Markup Strategy for Tables<table border="1"> <thead> <tr>

<th id="c1"> Course </th><th id="c2"> Time </th><th id="c3"> Day </th><th id="c4"> Prerequisiste </th><th id="c5"> Instructor </th>

<tr></thead><tbody><tr>

<td headers="c1">211</td><td headers="c2"> 11:30 pm -1:00 pm</td><td headers="c3">MW</td><td headers="c4">None</td><td headers="c5">McDonald</td>

</tr><tr>

<td headers="c1">211</td><td headers="c2"> 10:30am - 12:00 pm</td><td headers="c3">TR</td><td headers="c4">None</td><td headers="c5">Luecking</td>

</tr>

<tr> <td headers="c1">212</td> <td headers="c2">5:45 pm &nbsp;- 9:00 pm</td> <td headers="c3">M</td> <td headers="c4">211</td> <td headers="c5">Carter</td></tr>

<tr> <td headers="c1">212</td> <td headers="c2">11:30 pm &nbsp;- 1:00pm</td> <td headers="c3">TR</td> <td headers="c4">211</td> <td headers="c5">Chan</td></tr></tbody></table>

Label Elements of Forms

<form action="Billing Info" method="post"><fieldset> <legend class-"TitleLarge"><b>Billing Information</b></legend><p><label for="firstname">First name (required):</label><input id="firstname" type="text" tabindex="1"></p><p><label for="lastname">Last name(required): </label><input id="lastname" type="text" tabindex="2"></p></fieldset>

</form>

Skip Navigation

Normal Page

Alt Tags(None)

Alt Tags (Descriptive)

Other Vision Issues

Screen MagnifiersColor Blindness:

8% male population 0.5% Female population Most common red/green

Photo Sensitive Epilepsy

Color Blindness

This is an Ishihara plate commonly used to check for red/green color blindness

Color Blindness

This is what a red/green color-blind person might see. Note that the digit (3) is practically invisible.

Mobility Impairments

Conditions with affect use of keyboard and mouse

Might be difficult, Might be impossible

Predictive typingSpeech recognitionAlternative input technology

Hearing Impairments

Few more issues:Captioned mediaOpen or Closed captioningAmerican Sign Language

Web Accessibility Initiative

Promote usability for people with disabilities

Goal of Universal AccessSet of guidelines which address 2

themes: Graceful Translation Make content understandable and

navigable

Web Accessibility Initiative Guidelines

Globalization

Web is growing all over worldNumber of Non English speaking

users rapidly increasingUsability issues involve use of

language and cultureThis processes is called globalization

Global User Population

Internationalization

Internationalization single design used world wide

Simpler textUnambiguous display of number,

currency, dates, and timesIsolate and remove culturally specific

language

Localization

Added cultural contextTranslation of web page into local

languageRelevant content

Text and Translation

Translation: human or automatic?Attention to writing styleExpression of dates, timesExpress currency in local termsLabel units of measurements

Languages Can Expand Labels

Page Layout

Unicode for character supportColor issuesIcon issues (including flags)Text Alignment (left vs. right)

International User Testing

International and local sites need user testing

More involved than traditionalTest success of translationInternational Inspection as

alternativeDifficulties dues to language gap

Personalization

Strategy for gaining competitive advantage

Added service for a userSpeeds task completion (I-Click)Can require loginCookiesDynamic

Privacy Concerns

No right to privacy in USPrivacy ContractsRequest of personal information can

cause users to leave siteHighly related to trust

Trust

Many factors affect trust:ContextPerceived SimilarityStanding in organizationBehaviorCertificationReferences

Fostering Trust

Help establish credibilitySecurity StatementSafe display of personal informationUse of secure serversConfirmation of all costsConfirmation of shipping address

Controlling Privacy

No standard for enforcing privacy in place

P3P standard developedEnforces and exposes site’s privacy

policyTools to inform users of compliance

with their selected privacy policy

Trust (P3P)

Trust (P3P)

Privacy Bird

Privacy Bird

Shows Embedded Content

Privacy Bird