This section introduces a few other languages and applications that web designers often use in addition to HTML when creating web sites. It highlights core accessibility issues and strategies for each, and points to outside resources for more information and guidance.
You can use HTML to control the structure, content and presentation of your web pages. Alternatively, you can leave structure and content to HTML, but control appearance instead with another markup language, Cascading Style Sheets (CSS, or .css files).
Using CSS (also sometimes simply called “style sheets”) to create your page presentation separates page appearance from the page’s content and structure. This has several advantages, including:
Once you learn how to use it (and it’s not that hard), CSS lets you control your webpage presentation more flexibly and easily, while (potentially) increasing accessibility. Compared with using tables or frames, CSS makes it much easier to control your layout while keeping the content linear and, therefore, accessible to screen readers. You can also use hidden CSS that won’t change your visual impact while making your sites more accessible to users with disabilities.
Figure 10 shows a web page with the host site’s style applied, and then how it looks with the styles removed. For pages styled with CSS such as this one, a user could then apply their own style to make it more useable for them. For example, someone with low vision might set the page to show a large, white font on a black background.
Note that even when using CSS, the content and structure you provide with HTML needs to follow the same guidelines as when you aren’t using CSS.
Also, don’t make your pages dependent on CSS – it is only for presentation and appearance. If you try to use it to control page structure, your pages will become less accessible.
See WebAIM’s introduction to style sheets at www.webaim.org/techniques/css, including a section on using CSS to improve accessibility with content that is invisible to users who don’t need it. The Access E-learning tutorial includes some tips on CSS within their HTML course module at www.accesselearning.net. The article at www.mcu.org.uk/articles/tables.html discusses the virtues of CSS vs. tables for layout.
W3schools offers CSS tutorials, 70 examples, and a CSS reference listing at www.w3schools.com/css. Also, Cornell’s CIT offers face-to-face training sessions on Getting Started with CSS. Visit the technical training schedule available at www.cit.cornell.edu/training to see when the next workshop is.
Accessible approaches and solutions are:
Plug-ins are computer programs that interact with a host application, e.g., a web browser, to accomplish a task that the host cannot do on its own. Plug-ins might be used to read particular kinds of files (e.g. using QuickTime to show a video), or play and watch presentations in browser (e.g., watching a Flash presentation).
Three things for web developers or designers to keep in mind about plug-ins are:
Several things you can do to make plug-ins generally more accessible include:
WebAIM compares media players (RealMedia Player, RealOne, Quicktime, and Windows Media Player) in this article: www.webaim.org/techniques/captions/mediaplayers. They recommend using players as standalone, rather than embedding them, to make them accessible.
WebAIM also hosts an article about using Flash accessibly, www.webaim.org/techniques/flash. The “Flash and Accessibility” article at www.usability.com.au/resources/flash.cfm provides a bit more detail, and you’ll find checklists at www.catea.org/grade/guides/flashmust.php. Adobe’s Flash Accessibility information is at www.adobe.com/accessibility/products/flash.