Search Engine Optimization Book

SEO BOOK

crawled page is that you can get your new sites, pages, or projects crawled quickly by linking to them from a powerful or frequently changing page.

The Index:

The index is where the spider collected data is stored. When you perform a search on a major search engine, you are not searching the web, but the cache of the web provided by that search engine (its index).

Search engines organize their content in what is called a “reverse index." It sorts web documents by words in a language. When you search Google and it displays 1-10 out of 143,000 website it means that there are 143,000 web pages which either have the words in your keyword phrase on them, or have inbound links containing the words in the phrase.

Search Interface:

The search algorithm and search interface are used to find the most relevant document in the index based on the user search. First the search engine tries to determine user intent by looking at the words the searcher typed in. The search engine breaks this down via keyword vectors and compares this to their database to find the most relevant results.

In most major search engines a portion of the relevancy calculations are stored ahead of time and some of them are calculated in real time.

Search Algorithm Shifts:

Search engines such as Google and Yahoo! often update their algorithm dozens of times per month. Often times when you see changes in your rankings it is due to an algorithmic shift or something else outside of your control. Usually if you change something on a page it is not reflected in the search results that same day or the next day.

Relevancy wins distribution!

The more times a search leads to desired content, the more likely a person is to use that search engine again. If a search engine works well, a person does not just come back, they also tell their friends about it, and they may even download the associated toolbar. The goal of all major search engines is to be relevant. If they are not they will fade (as many already have).

Origins of the Web

The web started off behind the idea of the free flow of information as envisioned by Tim Berners-Lee. He was working at CERN in Europe. CERN had a somewhat web-like environment in that many people were coming and going and worked on many different projects. This helped lead some of the ideas behind his eventual World Wide Web creation.

Tim created a site which described how the web worked and placed it live on the first server at info.cern.ch. Europe had very little backing or interest in the web

4