According to Matt Cutts, there are over 100 factors that affect search engine ranking. For those of you who don't know, Matt is a Google guy guru, he is employed by Google but writes an independent blog and shares information related to Google and search engine optimization. Unfortunately, of those 100 items that account for search engine ranking, there are only a few that webmasters can actually control.

Unless you are a interested in an exercise of futility, it is important to only focus on those ranking factors that you, as a webmaster, can control and influence.

What are Search Engine factors do webmasters control?

Outside of the obvious (webpage title and description) those items which the webmaster has the most control are: PageRank, TrustRank, Anchor Text, Keyword Density, Domain Age, URL, and Relevant Links.

How can a webmaster use these items to help ranking?

1. First off–the obvious, each and every web page should have a descriptive page specific title and description. The title, description, and header tags are channels to communicate the most important details of a specific webpage. They should be used effectively, but not be abused. The web page should make use of h1 and h2 tags (header tags) to emphasize pertinent keywords and phrases.
2. Particular attention should be paid when formatting urls. Keywords related to the webpage can and should be used in the webpage urls. Use hyphens rather than underscores between the keywords. Search engines are designed by developers and programming languages will recognize a hyphen and distinguish separate words, while an underscore blends the words. Keywords in the URL should not be abused, as search engines do not appreciate excessively long urls. Avoid using characters like ID= in the URL as many search engines will see it as a unique session ID and not spider the contents of the webpage.
3. The website's navigation depth should not exceed 3-4 levels. The shallow website depth will make a search engines deep crawl easier, ensuring that will be able to spider the entire contents of your website. If you add a new page and wish for it to be spidered quickly add a link to it from an existing spidered web page.
4. Domain hosting and location do matter! A .uk domain and a webhost located in the UK will increase the domains search engine position in any .uk search engine. If you are targeting a specific region or market consider purchasing a local domain.
5. Obviously you control the websites content; bad content or no content means no incoming links. Good content has the potential to attract good quality unsolicited links.
   
   What kinds of content generally attract quality links?
   
   
6. The idea is develop quality content that will result in incoming links. Think of JibJab, they portrayed a controversial subject in a humorous way without alienating their audience. While JibJab was able to garner a lot of attention, its a tricky tight-rope to walk. Consider adding tutorials that explain a specific technology, create a niche directory or a topic specific glossary, post industry news, maintain a blog with fresh content, or write how to articles.
7. Take advantage of your content. If you write a press release don't just send it to the editors, add it to your website in a press center. Submit the press release to public relations websites. There area a number of press related websites like PRWeb that are really good and all will result in good quality incoming links back to your website. Also add your press release(s) to an RSS feed, not only with this communicate with your customers that new products or updates are available but you will also benefit from links from RSS search engines and directories.
8. When you post a release or content that has genuine value, use social bookmarking tools (like digg, del.icio.us, furl) to bookmark the contents. These social bookmarking sites are becoming increasingly important in weighing the value of a site. The large search engines do not yet use social bookmarking in their algorithms, but it is quite possible and highly likely that they will in the future. If the webpage/content has genuine value others will social bookmark it as well. The bookmarks are viral and with increasing popularity there is more emphasis placed on the content. Additionally, bloggers notoriously skim social bookmarking sites for content to write about which will result in additional links. Keep in mind that in order to bookmark a webpage, it really must have genuine value.
   
   Before we talk more about links, there are a few warnings worth mentioning.
   
   
9. What are the link warnings? The first is to attain links gradually, search engines prefer links obtained over time rather than links achieved all at once. Avoid link schemes, link farms, or overt reciprocal links, they can be time consuming and have very little benefit. Avoid links on the C block. If you own multiple domains, be sure not to triangulate links. Search engines have become wise to this and they prefer a linking scheme that is more like a star (or web).
10. What keywords should you optimize for? When determining what keywords to optimize a website for, there are a number of tools that will assess the number of times that a keyword or phrase is searched on, the number of websites/webpages competing for that keyword or phrase, and rate the phrase. Obviously, the terms that have more searches and less competition are the best to optimize for--if, and only if, they relate to your product or service. If you optimize for terms that are either too broad, you will likely increase traffic but decrease your conversions. It is really a balancing act. Two of the more popular tools available are Keyword Discovery and Word Tracker. Also, talk to friends or family members and ask what phrases they would use to describe your product or service. You might be surprised with the terms they use. Consider optimizing for regional variations, look at the variety of terms used to describe soda - tonic, pop, soda, soda pop, or cola all are relevant and popular but only within a specific region. Examine web logs to determine what your users are using, look at the language used in emails and forum posts and consider optimizing specific pages for popular descriptive terms.
11. And finally, use competitive intelligence to locate links and keywords. What are your competitors using? Analyze the adwords they bid on, look at their meta tags, look at their anchor links.

There is a wealth of information out there, no real mystery to it, so use it to your advantage.