How do Search Engines Work?

In order to use Search Engine Optimization one must know full functionality of Search Engines. The working is as follows:

Search Engines for the general web do not really search the World Wide Web directly. Each one search a database of the full text of web pages selected from the billions of web pages out there residing on servers. When you search the web using a search engine, you are always searching a somewhat stale copy of the real web page. When you click on links provided in search engine search results, you retrieve from the server the current version of the page. Search engine databases are selected and built by computer robot programs called spiders. Although it is said they “crawl” the web in their hunt for pages to include, in truth they stay in one place. They find the pages for potential inclusion by following the links in the pages they already have in their database (i.e., already know). They cannot think or type a URL or use judgment to decide to go look something up and see what’s on the web about it. Computers are getting more sophisticated all the time, but they are still brainless. If a web page is never linked to in any other page, search engine spider’s cannot find it. The only way a brand new page - one that no other page has ever linked to - can get into a search engine is for its URL to be sent by some human to the search engine companies as a request that the new page be included. All search engine companies offer ways to do this.