Rule 1: Improving your relevance = improving your rank.
There are many, many factors that make up a search engine’s ranking algorithm and there is no one person that can give you an exact formula. In fact, the formula may change based on your industry or keywords. Most SEO experts will agree, however, there are some known factors that have influence beyond the basic level of search engine optimization.
If you are trying to achieve rank for a keyword that is low in competitiveness, you may not need to consider these advanced SEO factors. But, in some circumstances every little boost is important.
Pages that are more than 2-3 levels deep within a website tend to achieve rank less often than pages at root level.
www.mysite.com/keyword.html versus www.mysite.com/content/pages/category/keyword.html
Site maps (linked from the home page) are used by search engine robots to easily find pages within your site.
Search engine robots follow text links much easier than image or script links so don’t make it harder.
URL’s that contain keywords are a ranking factor for some engines. Even if your domain name doesn’t contain your keyword; you can still insert it by using a page naming methodology like this:
www.mysite.com/keyword.html instead of www.mysite.com/contentID4.html
Search engine robots
Search engine robots will note the date your content changes and what has changed since their last visit. Sites that update content more frequently will get indexed more frequently.
Search engine robots typically do not index your entire site in one visit… it is not known how many pages or how long each visit will be but it is beneficial to make sure your content is as accessible as possible… shorten your code, use consistent linking and a site map. Pages that are too deep may never get indexed unless they have a large link popularity.
Validate HTML! Search engine robots can skip part or ALL of your page if they encounter unrecognized or garbled coding.
Advanced SEO techniques encompass many “little” elements but when they add up, it could make the difference you need to boost your search engine positioning. If in doubt, see rule number 1 (above).