Even though there are a lot of different ways to create a web site, most pages have a similar architecture. In the parlance of SEO, these segments are broken into what are called “blocks” which a search engine can better classify. It should be noted that different algorithms will give different weights to each block, but some common sense should prevail in the importance of each segment. Here are some of the aspects of a web page that a search engine may consider:

• Header – The header section of your site may contain elements like the H1 tag, a phone number, or visual information that is brief but very informative to the customer. You might have navigation links, tabs, or breadcrumbs in this part of the page. A search engine should consider the significance of this block to be above average.
• Navigation – Search engines are going to use the navigation links to discover the relative importance of other pages on your site. However, extraneous information in this section may not be as weighted since navigation only gets read when you need to get to another page. If you have a bunch of outbound text links under your normal navigation, their placement may be suspect.
• Body Content – (Note that the relative placement of the body content block may be a factor.) For an informational site, the body content should have very high importance. For people who are getting SEO value from link purchases, placement in the body content among text is generally considered to have a higher value than a link floating around in the footer or right margin. For “white hat” purists, the body content is going to be where well-written and topical information should reside. As always, this content should closely agree with the page title.
• Footer – The footer block will normally contain redundant navigation, links to other sites your company may own, your physical address, fax number, and other useful data. A person may get to the footer after reading the body content and navigate from there. A text link to another site may have a higher chance of being considered to be spammy, especially if it resides among 16 other text links for marginally relevant sites.
• Margin – What goes in your right margin block, assuming you have one? You might have a blogroll, a series of text links, or even a form. Opinions vary on the value of this block, but there is some consensus that a block containing a bunch of suspect links isn’t going to help a “good” link that gets put in the same piece of real estate.
• Visual Elements – Blocks for visual elements like images and graphics may become more important over time, since search engines are getting better at reading the text inside image blocks, and recognizing objects in pictures. As always, good image labeling and alt tag association may help the page as a whole, since a picture of a dog on a page about dogs reinforces relevance.
• Advertising – A block recognized as advertising is likely to get a below average value. This doesn’t mean you shouldn’t advertise on your site, but links from this block may not get much weight, and too many blocks of advertising could lower your score altogether. Search engines probably won’t want to serve up pages full of ads when they make their money selling the same thing.
• Blog Comments – A block of blog comments (which would naturally be recognized beneath the block showing blog content) is going to get less weight overall. It doesn’t help to have spammers who try to put links to their own content (whether it’s an SEO link or not may not matter), or run-of-the-mill crackpots who go off on a tangent that is totally irrelevant. In this case, a lower segmentation value for blog comments is probably helping the blogger get found.
• Forum Comments – Forum comments can be very useful when they answer common questions. Some thought has been given to the idea that the actual content of the forum posting has more value than the signature of the comment block, which is devalued because it may contain spammy links.
• Miscellaneous links – Some of the cheaper “link submission” sites out there will put your site’s link on pages with several hundred other links. A block of these links will already have low value because link popularity is divided by all the outbound links on the page, but being in a block of such links would further diminish the value. Also, sites that do sitewide links in certain page segments are also easy to identify, and buying links like these is not recommended.

To understand why search engines may think that segmentation is important, you only need to see that patents have already been filed for search algorithms by Microsoft, Yahoo, and Google. The process of segmentation allows for better understanding of what a person may find important, and what a person may ignore. Eye tracking studies have already shown that people have trained themselves to bypass advertising content on web pages, so a search engine would likely consider any content in an advertising block to have minimal relevance. In the same way, blog comments, which may have been a useful SEO trick for generating content and links, are going to get less importance because of their profile compared to the actual blog posting.

The most important takeaway for the SEO professional is to ensure that content and links are placed on parts of the page where they will have the most impact. The practice of stuffing content below the footer is going to have less and less relevance if the “meaty” portion of the site is considered to be more adjacent to the header and side navigation. Secondarily, a site with an unusual design, or one that can’t be deciphered by a search engine, may lose the content power that a properly segmented site can provide. For link building purposes, links to your site from suspicious areas aren’t going to get much value, and too many “bad segment” links could be an algorithmic indicator of paid link acquisition. At Web.com Search Agency, understanding page segmentation is also very important for helping our SEO clients craft websites that are search engine friendly and more useful for customers, which can be a “win-win” situation when the site gets good search engine traffic and makes the client more money.