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Imagine that you are hosting an event. You are glad so many people have arrived and want to make a good impression so you want to have lunch served quickly and conveniently. You order pepperoni pizzas and place them on a table where many people can access them at once. Your guests are hungry and eagerly approach the waiting pizzas but as you watch you see some guest moving around from box to box, getting frustrated and eventually leaving the table disappointed, angry and unable to partake in a basic part of the day: eating. What happened? You didn’t think about the different needs of your guests and excluded those who have wheat allergies, gluten allergies and lactose intolerances as well as those who do not eat meat, pork or dairy products and those who need low fat, low sugar or low carbohydrate meals. Instead of making your guest feel welcome, comfortable and able to quickly get what they need, you disappointed and excluded about 15% of them. If your web page is not accessible then it is having the same effect on all of your web visitors who need alternatives ways to access the web content you are serving up.

Big Ideas Summary

Web accessibility is a part of inclusive design that means that people, particularly people with disabilities, are able to access information on a web site and use a web site effectively. There are many reasons why it may be hard to use a web site: the content may not be in your first language, you may have a broken arm, you may have no speakers, your wireless mouse batteries might wear out, you may be driving and unable to look at the screen, you may be new to using the internet, or you may have limited data and not want to download large images or videos. These things are called “contextual or temporary disabilities.” An accessible web page would provide you with an alternative way to access the content on the web page in each of these situations. The same features that enable someone who has a hearing, vision or cognitive impairment to use a web page help other people use a web page too. Guidelines for web accessibility have been made by the World Wide Web Consortium which is also known as W3C. The Web Content Accessibility Guidelines or WCAG (now in its 2.0 version) that were developed by W3C ensure that people with physical and contextual or temporary disabilities can perceive, understand, navigate, and interact with the Web, and that they can contribute to the Web.

Web accessibility is seen as even more urgent as many populations in the world have greater numbers of seniors than ever before and increased disability occurs with increased age. Web accessibility encompasses all disabilities that affect access to the Web, including visual, auditory, physical, speech, cognitive, and neurological disabilities. For those of us who use a keyboard, mouse, and our vision and hearing senses to use the web, it can be hard to understand how a web page or a computer could be used by someone who does not use these tools or sense to access the web and uses alternative access methods instead. The document "How People with Disabilities Use the Web" describes how different disabilities affect Web use and includes scenarios of people with disabilities using alternative access methods to access and use the Web.

Millions of people have disabilities that affect their use of the Web. Currently most Web sites and Web software have accessibility barriers that make it difficult or impossible for many people with disabilities to use the Web. Legislation such as the Accessibilty for Ontarians wth Disabilities Act (AODA), the Americans with Disabilities Act (ADA) and international agreements such as the UN Convention on the Rights of Persons with Disabilities (UN CRPD) have begun to set standards for accessibility that are usually based on WCAG.

The Four POUR Principles of Web Accessibility

The Web Content Accessibility Guidelines and Success Criteria are organized around the following four principles, which lay the foundation necessary for anyone to access and use Web content. Anyone who wants to use the Web must have content that is:

  1. Percievable - Information and user interface components must be presentable to users in ways they can perceive.
    • This means that users must be able to perceive the information being presented (it can't be invisible to all of their senses)
  2. Operable - User interface components and navigation must be operable.
    • This means that users must be able to operate the interface (the interface cannot require interaction that a user cannot perform
  3. Understandable - Information and the operation of user interface must be understandable.
    • This means that users must be able to understand the information as well as the operation of the user interface (the content or operation cannot be beyond their understanding)
  4. Robust - Content must be robust enough that it can be interpreted reliably by a wide variety of user agents, including assistive technologies.
    • This means that users must be able to access the content as technologies advance (as technologies and user agents evolve, the content should remain accessible)

If any of these are not true, users with disabilities will not be able to use the Web. (source:

Accessible web pages are flexible and responsive to the user’s needs and preferences which means that the web page can do its job of getting information to those who want to access it.


Web Content Accessibility Guidelines (WCAG) Overview:

Web Content Accessibility Guidelines (WCAG) 2.0:

How people with Disabilities use the web:

Introduction to Web Accessibility:

Web AIM Accessible web design resources:


A chapter by Shawn Lawton Henry on web accessibility:

A book on web accessibility that is great for web designers and people new to the topic:

An Interesting book on the interaction between disability and online spaces (more theory than practical):
Goggin, G, & Newell, C (2003). Digital disability: The social construction of disability in new media. Lanham, USA: Rowman & Littlefield Publishers .

Twitter Accounts to Follow

@webaccess4all - USA based Twitter account about web access. Not all content relavent in a Canadian conte@webaccess4all xt but, lots of useful information about why access is important and programming how to's

@idrc_ocadu - Research and development centre at OCAD University working to ensure that emerging @idrc_ocaduinformation technology and practices are designed inclusively. Home of the Outside-In Project; a good resources in a Canadian context.

@w3c_wai - W3C Web Accessibility Initiative (WAI) develops strategies, guidelines, and resources to help make the Web accessible to people with disabilities.

@googleaccess - The official Twitter account for Google's accessibility team.

@MSFTaccess - Official news, updates and insights from Microsoft Mobile Accessibility.

@a11yTO Toronto Accessibility & Inclusive Design meetup: Accessibility Camp Toronto coming in fall of 2015.


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