Human Memory

Our memory plays a vital role in the usability of a Web site. Experience with a Web site provides us with the knowledge of, and a sense of comfort with, a particular place or system. It enables us to use a Web site successfully every time we return to it with minimum wasted time and effort.

This is why it is most important that Web designers try to minimize the number and amount of changes to a Web site layout and navigation system. Yahoo!'s Web designers realized this important usability feature a long time ago. This is why their Web site has changed little in the last few years.

I have seen first hand how a change in a site's layout can seriously affect a user's ability to use it. I recommend that you avoid merging the content of one Web site with another and redirecting the old site's traffic to the new site's home page.

Existing users of the old site will find that all the knowledge gained has been rendered useless. A lot of users will use another site they are more familiar with, if the new site requires too much effort and time to learn to use.

User-Centered Design (UCD) >>>