With the advent of XML site maps, it seems like no one talks any more about the importance of having an html site map on your website. This is simply the online equivilant of a table of contents for your site. It consists of one or more pages of text links that serve four very important purposes:

• To permit human visitors to see what your website contains and to easily find what they want on your site.
• To provide an easy way for the search engine spiders to find all of the pages on your website through these links.
• To impart good link reputation to all of the pages of your site.
• To help you control the PageRank distribution on your site.

Just about everyone understands and puts to good use the first two concepts. However, the second two tactics can give you that extra edge you may need to move your most important landing pages up in the SERPs.

Site Map Styles

There are several styles of site maps, some better than others and different ideas on how they should be structured and linked.

Traditional Site Maps

Most webmasters will place a link to the site map page on every page on the site. This can be done through a link in the navigation, but is most typically done in the page footer. Then, no matter which page a Search Engine spider or human visitor lands on, they are just one click away from the this table of contents.

Since every page links to the site map page, the site map typically gathers a great deal of PageRank, which it then distributes to the other pages of the site through its links. This tends to distribute PR rather evenly across most of the pages of the site.

If you’re of the opinion that PageRank should be allowed to accrue and be distributed naturally, this is probably the type of site map you want on your website.

Autogenerated Site Maps

Some CMSs (Content Management Systems)-including WordPress, if you use a site map plugin-can automatically generate an html site map for you. This is convenient and can be the only practical solution for sites with thousands of pages. However, from an SEO standpoint and for visitor usability it is not always ideal.

These site maps typically create their links from the titles of the pages, which can be good or bad, depending on how well and how thoroughly the site is optimized with unique, descriptive page titles. Sometimes they are logically organized according to the hierarchal structure of the site, which is good for human visitors. Other times, they are placed alphabetically on the page, which is not that useful for humans seeking content.

Another disadvantage is how large numbers of links are usually treated with an autogenerated site map. They tend to either place all the links on one enormously long page or to link from the first page of the site map to additional site map pages.  The first is method is bad because Google has stated that they don’t want more than 100 links on any page and it makes it difficult for humans to find what they are looking for. The second method allows the first page of the site map to accrue the most PageRank and additional site map pages become less powerful than the first page.

While careful organization can overcome these disadvantages, it’s somewhat rare that the webmaster or SEO takes the time to do so. However, you can certainly use a hybrid technique by beginning with an autogenerated site map and then tweaking it for the best of both worlds.

Customized Site Maps

In my opinion, customizing the Page Rank distribution (PageRank sculpting) of a website is a very worthwhile tactic. On smaller sites that already have some decent PR, it can really boost them up in the SERPs.

On gigantic sites, you must be very careful not to do more harm than good and I usually concentrate on sculpting the PR only for the most important pages. Site maps are a critical tool in this process.

See HTML Site Maps Part 2 to learn more about this.