Usability is a measure of how easily people can use your web site. When a person comes to your site, he or she should be able to see immediately how it is organized and how to navigate from one page to another and back again. Your audience should be able to find the information they need without difficulty and remember how to access that information in future visits. Your web pages should work on a variety of browsers and platforms .

It is a good idea to test the usability of your web site as you develop it. Identify a few members of your target audience and perhaps a few members of secondary audiences. Assign specific tasks, for example, navigating to a certain page or finding a piece of information. Note whether your testers can complete the tasks and how long it takes them to do so. It will quickly become apparent which aspects of your site you should change and which you can keep.

As you go along, check your web site under any of the following conditions that apply to your users:

1. Multiple browsers (Netscape, IE, AOL, Safari, Mozilla).
2. Multiple versions of the same browser (Netscape 4.79, Netscape 7).
3. Multiple platforms (Windows, Mac, Unix, Linux).
4. Multiple browser window sizes (note: browser window does not equal monitor size).
5. Multiple computer monitor resolutions (from 640x480 to 1600x1200).
6. Disable/enable various browser tool bars.
7. Disable image viewing in the browser preferences.
8. Disable JavaScript in the browser preferences.
9. Disable style sheets in the browser preferences.
10. Change font size in browser preferences.
11. View with alternate Internet appliances (PDA, etc.).
12. View with actual screen-readers (in Morris Library).
13. Validate with online services.
14. Design for users who don't access a page from your home page.