In explaining Search Engine Optimization (SEO) to prospects and clients alike it seems that there are a lot of companies that look at search engines and SEO as a mystical realm where one only hopes to rank well. Because of this, I have decided to try to simplify the concept of how search engines work so that the methods for search engine optimization and the varying importance of each method can have better context.
After everything is said and done the goal of search engines is simple: To provide searchers with the absolute most accurate, high quality, relevant results to any search performed. Well, how do they go about doing this?
First, search engines crawl and index content from websites to figure out what the specific pages on a website are all about. By analyzing the words used, how often they are used and many other criteria, the search engines make their own determinations on what each web page is about. So, if a web page is focused on a new species of baboon the content should actually be focused on this mysterious baboon. On-site or on-page search engine optimization focuses on making sure that search engines will get the right idea on what a page really is about (no faking, no spoofing, no cheating).
Now, step into Google's (or Bing's or Yahoo's) shoes. If you know that there are thousands, or even millions of pages out there who want their website to be seen above all other sites, would you trust them when the content on their page says it is about bumpy the baboon? My answer would be: "Sort of..." It is just like having a salesperson come to your door and make claims about a product they are selling. You may suspect that they are telling the truth, but you would most likely feel skeptical and need to research it further to feel confident.
The ways that search engines make sure a website is relevant, accurate and high quality for a specific search term are by looking at factors a website can't fake very easily. The first of these methods is what I call "checking references." I know if the salesman above claims some things that sound like they might be beneficial and I am interested I am going to want some references, and the more the better. Search engines want as many of these as they can get. They won't be satisfied with just a few references and they have to come from other trusted sources that the search engines already believe are credible. Since search engines crawl websites the way they check these references are by finding other websites that are linking back to the website in question.
Since search engines care about relevancy and quality related to a search being performed when checking references search engines are considering:
- How much does the search engine trust the reference (how many other high quality sites are linking to the reference site)?
- What is the content on the page that links back to the site in question?
- What is the text surrounding the link back to the site in question?
Assuming that many of the references checked are good and show that the page must indeed be about bumpy the baboon the search engines will increase the relevancy and quality score for the page, leading to the page coming up higher in the results when people search for "new baboon species" (this may actually be an interesting search... I don't know since the baboon thing was just a possible topic that jumped into my head). The practice of building links from external websites back to your own is called link-building and is the major method (and I would argure the most important) of off-site or off-page SEO.
Finally, because the best search engines are very tenacious at finding great results they are going to also consider websites that get a lot of traffic as more important than websites that get little traffic. It makes sense that if everyone is going to one coffee shop instead of another that the one with the line of people is probably better.
Now, I realize that the search engines' algorithms are very complex and that only the insiders know the true secrets to the nuances of the algorithms. Even so, from all my experience it really comes down to a logical explanation of what makes sense in order for search engines to provide the very best, most accurate, high quality results for a specific search.