The term “site map” has multiple meanings when it comes to websites.

First, there is the site map we create when we start planning a website. This map is a visual representation of all of the pages on the site and of their organization. It typically looks like an organizational chart, with the home page at the top, the main site sections underneath, and the individual pages right under each section. Here’s a sample:

This map helps both clients and web developers to see the whole picture and to understand the hierarchy of the website. Sometimes color codes are used to denote specific functionality. On medium to large websites, web developers will ask for approval of the site map before starting on the design.

The second type of site map we see, is the one actually offered on the website itself. A link to this map is usually found in the footer and it provides a complete list of all of the pages on that website in their hierarchical order. It can look like the simple outline below:

This map is a last resort help feature for users. If the navigation is set up well, users will find what they need through it and will not need to visit the site map. The hidden advantage of this site map is that it also helps search engine bots find pages on the site. Site maps can improve search engine optimization of a site by making sure all of the pages can be found. This is even more important when a site’s navigation is done through Flash or Javascript menus that don’t include actual links. Most search engines only follow a few pages, so the larger the site, the more useful the site map.

Finally, there’s the XML site map. This map was introduced by Google as a way to account for dynamic pages that are only available through the use of forms and user entries. The map is used to show the web crawler how these pages can be found. Google, MSN, Yahoo, and Ask use the same protocol, so having an XML site map lets the four largest search engines have complete and updated page information. These maps look more like code:

The XML site map does not guarantee that your site will be indexed or that all of the pages will be seen, but it is the best way to submit information about your site to the search engines.