Much of the technology that makes the Web "interactive" more so now than ever, comes in the form of browser-compiled programming languages, additional software that enhances the features of a web browser, and new web page markup languages. These kinds of features give a web page more appeal in the form of interactivity and flashy design as well as increased utility. The current trends in web page design point towards a more user interactive Internet, mostly prompted by the common need not to just relate information, but to make it interesting and more usable. Unfortunately, many of the attempts to make the information more exciting, lead to making it unavailable to many. JavaScript and Java applets are now more commonplace and supported but still have compatibility and accessibility issues. Additionally many people have problems with helper applications, plugins especially, in the form of software configuration difficulties. These and other advanced features can potentially impede the usability and accessibility of a site.
JavaScript and Java Applets
Currently, the most widely used technique for making web pages interactive is the use of JavaScript. Every major graphical browser has support, however partial or proprietary, for JavaScript, and its use on the Web is quite evident, from the simple "flying" graphic to managing large forms. But as mentioned previously in the section pertaining to browser compatibility, there does not exist a unique standard to which all browser makers adhere. In other words, although there are different "versions" of JavaScript, they are not guaranteed to work on all browsers. This can cause fatal errors when the script is compiled.
Another advanced feature commonly used in web design is the Java applet. Much of the interactive content in the past, especially animated banners, has been through the use of applets. Java programming differs from JavaScript in that Java is a "true" programming language, i.e. it is primarily object-oriented. Java applets are slowly being phased out of use on the Web in favor of DHTML, Flash, and Shockwave. Many browsers have, and indeed still do have trouble with Java applets in the form of the compilation engines that each individual browser uses. In web development, the selection of applets that work under a wide variety of conditions is essential. It only takes one problem with one type of browser to single out a significant section of the web-browsing population. Additionally, most applets are anywhere from 25-50k in size, which limits the developer's options if a small, fast-loading page is desired.
Java applets and scripts that are used on web pages must be compliant with the W3C recommendation for alternative means of display. JavaScript must not be used to generate essential content, as text-based browsers and screen readers will ignore JavaScript altogether.
Browser Extensions
The newest features that make the Internet more interactive and flashy come in the form of "browser extensions" or helper applications. This category includes Macromedia's Flash and Shockwave technology, and Adobe's Portable Document Format (PDF). The major issue with this kind of technology stems from the fact that an additional program is needed to interact with the browser in order for the page content to be displayed. This causes problems with large downloads, buggy software, and cumbersome setup and installation. Many inexperienced viewers of a web page don't have a clear understanding how the Internet works, which is fine. The important point is that if "plugin" technology is used, it should be made clear to the audience where to get the software and how to install it. Additionally, since plugins are inherently non-accessible, alternative content must be provided to provide the same information the plugin feature does.
Image Maps
Another attractive kind of advanced HTML technique is the use of image maps. They must also be used with extreme caution. Image maps are large, cumbersome, and definitely inaccessible. Another problem with image maps is many browsers can not properly display the "alt" tags for the them. Because of this, image maps can impede the accessibility of a page. If using an image map cannot be avoided, it is imperative that the exact same content, especially links, are repeated in the vicinity of the image map. Additionally, these elements are more often than not server side. This means that any kind of interaction the user has with the map has to be relayed to the server and back before any action can be taken on the side of the browser thus slowing down the interaction between the user and web page.
Server Side Includes
Another kind of server sided issue is the use of Server Side Includes. SSI is extremely helpful in the creation of database pages, large sites that have the same features on every page, and in the handling of CGI scripts. Using SSI requires a general knowledge about how information is transferred to the remote computer from the server, and vice versa. The most helpful feature of SSI is the ability to include other "pieces" of HTML code into any document. In this manner a sidebar or footer could be generated on every page on a site and thus make future maintenance easier. Care must be taken however, to make sure the included HTML is "stripped" and free from extraneous code. As of this writing, no accessibility problems could be discerned concerning the use of SSI.
Due to the nature of the Wind Web Service's goals, any use of these kinds of advanced features must also be decided with accessibility in mind.
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