Scripting
Scripts that are OK, and those that are
a problem
FrontPage Hover Buttons
Resources
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Scripting is often used by web-designers to create dynamic material on the web page. For instance, menus that open when the mouse hovers over them, change colors, dynamic links, etc. are created with scripting. Usually JavaScript is used.
Scripts that are OK
Some scripts are OK. Javascript is sometimes used to make a button change to appear indented, or to change the color of the words in a hyperlink when the mouse is moved over the image.
As long as the CONTENT of the image or hyperlink does not change, this type of scripting is appropriate. For instance, if the image contains the word "Home" and when the mouse hovers over the word it changes color, but still says "Home", this requires no special modification for accessibility.
FrontPage Hover Buttons are Not OK!
FrontPage uses a component called Hover Buttons which appear to be completely accessible because they only change color or "glow" when the mouse hovers over them. However, they are not accessible. They are not accessible because they are not using JavaScript to accomplish this feature. Instead, they are using an applet which cannot be read by screen readers. The links contained within the Hover buttons will be completely missed. If you use Hover buttons, you must also create the same links as basic text elsewhere on your page.
Some JavaScript is not OK without work to make it accessible. If you JavaScript has menus that expand and reveal new information or change the content, you will need to make an accessible version of that menu or content in the <NOSCRIPT> section of your page.
Resources
Trace Center's Accessible JavaScript page
WebAIM Tutorial on Accessible JavaScript & DHTML
