Beginners Guide to SEO by Rand Fishkin of SEOmoz.orgSections in this guide:Prologue: Who is SEOmoz and Why is this Guide Free? A: What is SEO? oWhy does my company need SEO? oWhy do the search engines need SEO? oHow much of this article do I need to read? B: How Search Engines Operate oSpeed Bumps and Walls oMeasuring Popularity and Relevance oInformation Search Engines Can Trust oThe Anatomy of a HyperLink oKeywords some havea highly specialized focus while others take a more broad and general approach. Optimizing a web site for search engines can require looking at so many unique elements that many practitioners of SEO (SEOs) consider themselves to be in the broad field of website optimization (since so many of those elements intertwine). This guide is designed to describe all areas of SEO - from discovery of the terms and phrases that will generate traffic, to making a site search engine friendly to building the links and marketing the unique value of the site/organizations offerings.Why does my company/organization/website need SEO?The majority of web traffic is driven by the major commercial search engines - Yahoo!, MSN, Google i.e. http:/www.url.com/page.php?id=4 it also analyzes the page that casts the vote. Votes cast by pages that are themselves “important“ weigh more heavily and help to make other pages “important.“PageRank is derived (roughly speaking), by amalgamating all the links that point to a particular page, adding the value of the PageRank that they pass (based on their own PageRank) and applying calculations in the formula (see Ian Rogers explanation for more details).Googles toolbar (available here) includes an icon that shows a PageRank value from 0-10PageRank, in essence, measures the brute link force of a site based on every other link that points to it without significant regard for quality, relevance or trust. Hence, in the modern era of SEO, the PageRank measurement in Googles toolbar, directory or through sites that query the service is of limited value. Pages with PR8 can be found ranked 20-30 positions below pages with a PR3 or PR4. In addition, the toolbar numbers are updated only every 3-6 months by Google, making the values even less useful. Rather than focusing on PageRank, its important to think holistically about a links worth.Heres a small list of the most important factors search engines look at when attempting to value a link:The Anchor Text of Link - Anchor text describes the visible characters and words that hyperlink to another document or location on the web. For example in the phrase, “CNN is a good source of news, but I actually prefer the BBCs take on events,“ two unique pieces of anchor text exist - “CNN“ is the anchor text pointing to http:/www.cnn.com, while “the BBCs take on events“ points to http:/news.bbc.co.uk. Search engines use this text to help them determine the subject matter of the linked-to document. In the example above, the links would tell the search engine that when users search for “CNN“, SEOmoz.org thinks that http:/www.cnn.com is a relevant site for the term “CNN“ and that http:/news.bbc.co.uk is relevant to “the BBCs take on events“. If hundreds or thousands of sites think that a particular page is relevant for a given set of terms, that page can manage to rank well even if the terms NEVER appear in the text itself (for example, see the BBCs explanation of why Google ranks certain pages for the term “Miserable Failure“). Global Popularity of the Site - More popular sites, as denoted by the number and power of the links pointing to them, provide more powerful links. Thus, while a link from SEOmoz may be a valuable vote for a site, a link from bbc.co.uk or cnn.com carries far more weight. This is one area where PageRank (assuming it was accurate), could be a good measure, as its designed to calculate global popularity. Popularity of Site in Relevant Communities - In the example above, the weight or power of a sites vote is based on its raw popularity across the web. As search engines became more sophisticated and granular in their approach to link data, they acknowledged the existence of “topical communities“; sites on the same subject that often interlink with one another, referencing documents and providing unique data on a particular topic. Sites in these communities provide more value when they link to a site/page on a relevant subject rather than a site that is largely irrelevant to their topic. Text Directly Surrounding the Link - Search engines have been noted to weight the text directly surrounding a link with greater important and relevant than the other text on the page. Thus, a link from inside an on-topic paragraph may carry greater weight than a link in the sidebar or footer. Subject Matter of the Linking Page - The topical relationship between the subject of a given page and the sites/pages linked to on it may also factor into the value a search engine assign