A site map is a graphical representation of the pages in a web site.
Usually arranged in a hierarchial fashion, like an organizational chart, a site maps purpose is
generally to list all the pages in the site so that search engine robots can find them.
For very large sites with static pages, a site map can be very useful
to site visitors (humans) if the visitor is looking for a specific page, or a specific topic.
However, for small sites, the primary purpose of a site map is to provide a pathway for search
engines to find all the pages. This is particulary true when sites have content that can not
Wikipedia has a very complete description of site maps and their use.
Refer to these pages:
There are 2 primary types of sitemaps, or site
maps. The first is an HTML site map; the second is an XML site map. A third type of site
map less frequently used is a text site map.
The HTML site map can be easily integrated into
the "look-and-feel" of a site. It's appearance is usallly in an organization format either
vertically or horizonatlly. An example of an HTML site map is this sites page
The XML site map was developed by Google to solve
a need for search engines to more easily index sites with dynamic pages, large sites, and sites
using interactive forms. The protocol was developed by Google and has since been accepted by
Yahoo!, MSN, and ASK.
The XML site map is a
file that lists the
URLs for a site. It allows webmasters and search marketers to include information about each URL
such as when it was last updated, how often it changes, and how important it is in relation to other
URLs in the site. Search engines are then able to crawl the site more intelligently. The XML
site map complements the robots.txt protocol. A robots.txt file is an exclusion protocol which
tells search engines what NOT to index, and is a widely accepted practice. By submitting site
maps to search engines, the webmaster informs the search engines about the site, and helps the
indexing of site.
It is important to remember
that having a site map, either XML or HTML, does not guarantee a web site will be indexed. And
if indexed, the site map in no influences the ranking of the pages. Ranking is dependent on
page content, link backs, and other HTML fundamentals.
The XML sitemap format is a
tagged format using UTF-8 encoding. An example from Wikipedia is illustrated below:
A comprehensive treatment of the XML site map is
Google Webmaster Tools.
Site maps, either XML or HTML
are placed in the public directory of a web site. The public directory is also often called
the root directory, or ht docs directory. The check whether a site may have a site map, type
the domain name plus the file extension. For example, to check for an XML site, in your
browser type http://www.yourdomain.com/sitemap.xml. To
check for an HTML site map, type http://www.yourdomain.com/sitemap.html
There are a number of great site map generator
tools on the market that can be used to generate an XML, HTML, or Text site map - or generate all 3
of them. Search on the phrase 'XML Site Map Generator'.