As you might know, JavaScript is not supported by all browsers and some users disable it. When JavaScript is used, it should not be relied upon. In such cases you will disable your visitor to access your content.You should avoid as far as possible implementing JavaScript, to avoid running risks on complications on the end users machines, or while government and other employees are required to disable this feature, for security or other reasons. Also there is a number of users who are very concerned about security issues and disable this feature too.The issue here is not only concerning users disabling JavaScript in their browsers. How many do so? 8%? What about cell phone users? How about sight impaired users? For those for whom changing the current window or popping up new windows can be very disorienting, because they cannot see that this has happened. And what percent are they?

According to Usability Expert Jakob Nielsen: "On the Web, usability is a necessary condition for survival. If a web site is difficult to use, people leave. If the homepage fails to clearly state what a company offers and what users can do on the site, people leave. If users get lost on a web site, they leave. If a web site's information is hard to read or doesn't answer users' key questions, they leave. Note a pattern here? There's no such thing as a user reading a web site manual or otherwise spending much time trying to figure out an interface. There are plenty of other web sites available; leaving is the first line of defense when users encounter a difficulty.

Web site accessibility is important to you. It is more associated with architectural thought, rather than Web Design.

Providing links that allow the user to skip directly to content, bypassing the navigation, enhances the accessibility of your web site. This is recommended for blind or visually impaired users, people who use screen readers, and also for text-browsers, mobile phones and PDAs (Personal Digital Assistants). These links are common on most US, UK, Irish, and other government websites, as well as many universities and private organizations.