Accessibility involves two key issues: how users with disabilities access electronic information and how web content designers and developers enable web pages to function with assistive devices used by individuals with disabilities.
For the user with a disability, the challenge is to identify tools that provide the most convenient access to web-based and other electronic information. For the web content designer/developer, the challenge is to remove the obstacles that prevent accessibility tools from functioning effectively. In many cases, these challenges are relatively simple to overcome, but sometimes the solutions require some additional thought and effort.
Defining disabilities
Assistive technologies
Accessibility standards
Why is accessibility important?
Defining disabilities
The range of disabilities is broad and difficult to categorize; however, it is important to have some sense of the scope of the issue.
Assistive technologies
Users with disabilities frequently rely on hardware and software to access web content. These tools, known as assistive technologies, range from screen readers to touchscreens and head pointers.
Impaired users of the web frequently use software called a screen reader to read the contents of a web page out loud. Two common screen readers are JAWS from Freedom Scientific and NVDA. Screen readers enable users to hear, rather than read, the contents of a web page; however, a screen reader can read only text, not images or animations. It is desirable; therefore, that images and animations be assigned text descriptions that screen readers can read. These text descriptions are called alternative text, or alt text.
Users with low vision often depend on magnification software. Some magnifier users utilize speech features within magnification tools or use magnifier software in conjunction with a screen reader. Two popular screen magnifiers are ZoomText from Ai Squared and MAGic from Freedom Scientific. Screen magnifiers increase the size of a portion of the user’s screen or the entire screen in order to make the content more visible. Screen magnifiers that provide a speech feature depend on the same accessibility information as screen readers.
Users with mobility issues may rely on the keyboard instead of the mouse to navigate web pages. For individuals with nerve damage, arthritis, or repetitive motion injuries, use of the mouse may not be comfortable or possible. Using only Tab and enter on the keyboard, it is possible for these individuals to negotiate a page with ease. Many users of the Internet have the capability to navigate without a mouse and are simply unaware of it. In Microsoft Internet Explorer, pressing Tab moves the focus of the browser among all available links on a page. (The dotted lines around links in Internet Explorer are an indicator of this capability.) Pressing Enter activates links, much like clicking a mouse.
In some cases, users may employ touchscreens, head pointers, or other assistive devices. A touchscreen allows an individual to navigate the page using her or his hands without the fine-motor control required by the mouse. A head pointer is simply a stick placed in a person’s mouth or mounted on a head strap that the person uses to interact with a keyboard or a touchscreen.
In these cases, it is very important that essential components of the page work without a mouse. Rollovers, pull-down lists, and interactive simulations are all examples of elements that typically depend on the mouse for user interaction. The designer or developer of these elements must ensure that keyboard-defined events are included along with mouse-defined events. A quick test using the keystrokes available in Internet Explorer can provide a valuable glimpse of the difficulties a web page may present for users with disabilities.
Accessibility standards
Accessibility standards help designers and developers of web content identify and address accessibility issues.
The Web Content Accessibility Guidelines (WCAG) 2.0 from the World Wide Web Consortium (W3C) represents the next generation of guidelines for accessible design. This standard consists of 12 guidelines, each with three checkpoint levels for individual success criteria for web developers to meet: Level A, Level AA, and Level AAA.
In individual countries, national standards are increasingly common. Rehabilitation Act is based on WCAG 1.0 Priority One checkpoints. These same checkpoints serve as the basis for standards in Australia, Canada, and many other countries. Standards developed more recently are utilizing WCAG 2.0 as the basis, including Germany and Japan, and other standards in development are expected to utilize WCAG 2.0.
For the user with a disability, the challenge is to identify tools that provide the most convenient access to web-based and other electronic information. For the web content designer/developer, the challenge is to remove the obstacles that prevent accessibility tools from functioning effectively. In many cases, these challenges are relatively simple to overcome, but sometimes the solutions require some additional thought and effort.
Defining disabilities
Assistive technologies
Accessibility standards
Why is accessibility important?
Defining disabilities
The range of disabilities is broad and difficult to categorize; however, it is important to have some sense of the scope of the issue.
Assistive technologies
Users with disabilities frequently rely on hardware and software to access web content. These tools, known as assistive technologies, range from screen readers to touchscreens and head pointers.
Impaired users of the web frequently use software called a screen reader to read the contents of a web page out loud. Two common screen readers are JAWS from Freedom Scientific and NVDA. Screen readers enable users to hear, rather than read, the contents of a web page; however, a screen reader can read only text, not images or animations. It is desirable; therefore, that images and animations be assigned text descriptions that screen readers can read. These text descriptions are called alternative text, or alt text.
Users with low vision often depend on magnification software. Some magnifier users utilize speech features within magnification tools or use magnifier software in conjunction with a screen reader. Two popular screen magnifiers are ZoomText from Ai Squared and MAGic from Freedom Scientific. Screen magnifiers increase the size of a portion of the user’s screen or the entire screen in order to make the content more visible. Screen magnifiers that provide a speech feature depend on the same accessibility information as screen readers.
Users with mobility issues may rely on the keyboard instead of the mouse to navigate web pages. For individuals with nerve damage, arthritis, or repetitive motion injuries, use of the mouse may not be comfortable or possible. Using only Tab and enter on the keyboard, it is possible for these individuals to negotiate a page with ease. Many users of the Internet have the capability to navigate without a mouse and are simply unaware of it. In Microsoft Internet Explorer, pressing Tab moves the focus of the browser among all available links on a page. (The dotted lines around links in Internet Explorer are an indicator of this capability.) Pressing Enter activates links, much like clicking a mouse.
In some cases, users may employ touchscreens, head pointers, or other assistive devices. A touchscreen allows an individual to navigate the page using her or his hands without the fine-motor control required by the mouse. A head pointer is simply a stick placed in a person’s mouth or mounted on a head strap that the person uses to interact with a keyboard or a touchscreen.
In these cases, it is very important that essential components of the page work without a mouse. Rollovers, pull-down lists, and interactive simulations are all examples of elements that typically depend on the mouse for user interaction. The designer or developer of these elements must ensure that keyboard-defined events are included along with mouse-defined events. A quick test using the keystrokes available in Internet Explorer can provide a valuable glimpse of the difficulties a web page may present for users with disabilities.
Accessibility standards
Accessibility standards help designers and developers of web content identify and address accessibility issues.
The Web Content Accessibility Guidelines (WCAG) 2.0 from the World Wide Web Consortium (W3C) represents the next generation of guidelines for accessible design. This standard consists of 12 guidelines, each with three checkpoint levels for individual success criteria for web developers to meet: Level A, Level AA, and Level AAA.
In individual countries, national standards are increasingly common. Rehabilitation Act is based on WCAG 1.0 Priority One checkpoints. These same checkpoints serve as the basis for standards in Australia, Canada, and many other countries. Standards developed more recently are utilizing WCAG 2.0 as the basis, including Germany and Japan, and other standards in development are expected to utilize WCAG 2.0.
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