SEO : It's All About Rules...

While each search engine does thing is a slightly different way, they are all pretty much the same:

1. A spider is not intelligent - it operates to instructions determined by people, eg.
   
   Find the page title and meta tags...
   Grab the text (and ignore all HTML, images, flash, and JavaScript)...
   Pay particular attention to anything in a <H1> tag, and within 100 characters of a <p> tag...
   Follow links to find more content...
   etc.
   
   
   
2. A search engine is a computer program, consisting of rules written by people, eg
   
   What is the page title? Is it relevant to the page content?
   What are the page keywords? And how often do I find them in the page text content?
   Is this page popular - how many other internal pages and external websites link to it?
   Are any of the websites that link to his page really popular?
   When was the page content last updated?
   etc
   
   
   

What rules would YOU create?

Think about what rules you would create if you were creating a search engine.

Then have a look at Google's guidelines to see how it compares (see www.google.com/support/webmasters/bin/answer.py?hl=en&answer=35769 )

What a search engine wants

1. Search engines LOVE :
   
   lots of well organized original content, contains words, pictures (even video)
   popular & relevant sources linking to your pages (indicates that your page must be important)
   
   
   
2. Search engines HATE :
   
   duplicate content, especially hosted on the same server
   something that looks too good to be true (like a very average web page with 10,000 links suddenly pointing to it)
   anything suspicious (like a keyword repeated too many times, or websites located on the same server linking to your site)

Therefore the sites that rank the highest in search results are usually the ones with the best content (which is good food for the search engine spiders, and, because it is great content, is the most linked to).