So, what is a site map?
A site map is a list of all main topic areas of a website, as well as sub-topics, if applicable. This serves as a guide as to what content will be on the average site, and is essential to developing a consistent, easy to understand navigational system.
The end-user of the website (aka your customer) must be kept in mind when designing your site. These are, after all, the people who will be learning about your service or buying your product. A good user interface creates an easy to navigate web site, and is the basis for this.
Here’s an example of a site map for a real client.