How Search Engines Work

Part 2 of Introduction to Search Engine Optimization

Last week, I talked about Search Engine Optimization, or SEO. What it is, why you need it, and who can do it. To understand search engine optimization, you need to understand how search engines work.

picture of men looking at public transit routes - search engine optimization

You can’t optimize your site if you don’t understand the way that search engines like Google and Bing work. Let’s learn how today!

You had two jobs…

Google and Bing, and the other search engines really have two basic things they do. First, search engines must “crawl” the internet. Second, those search engines have to compile the information they find and put it together so that users of their search engine can search that information.

Crawling and Saving

Imagine the internet as a map of a city or state. There are roads and streets and alleys and gravel roads. Those are links. There are homes and apartments and buildings. Those are sites.  Search engines send out robots that act like a car and it’s job is to find all the available roads and pathways of that state. When that car gets to a house, the robot stops, looks around and figures out where else to go on it’s search.

Or, if you will, imagine a subway. Each stop is a site that the search engine has to save and compile into its own database.

These robots can only see the code that each website is written in. It doesn’t see the web like we do. We’ll see how this shapes search engine optimization later.

You have Questions? We Have Answers

Users of the internet typically go to Google or Bing to find what they’re looking for. You and I don’t know every page of the web so we go to a search engine to look for what we want. A search engine’s challenge is to give the user the very best results it can based on what it finds. Search engines use two factors:

  • relevance – what is useful to the user
  • popularity – how many other people have found the results useful

The search engines employ complicated algorithms (if I knew what the algorithms did, I’d be in San Francisco…) to determine relevance and popularity of sites and then present the results to the user.

There are more factors that influence search results, but I think that this is a fine place to stop for now.

What do I do now for better Search Engine Optimization?

If you want to take some action on what you’ve learned here, perhaps these tips could work:


  • Make sure your website(s) are made for the user, not for the search engine
  • Sites need a clear hierarchy and text links. Every page should be reachable from one static link
  • Create useful, information rich sites and accurately describe the the content there
  • Create human friendly URLs with keywords that would make sense to a person


  • Make sure your site has a clean keyword rich URL structure in place
  • Don’t bury your content inside flash players, javascript, or ajax code and don’t hide links
  • Produce fresh content regularly and match keywords to what people might search for
  • Search engines can’t read whats on an image, so make sure that company names or information is elsewhere.


Search engines crawl and index sites on the world wide web in an effort to provide people with the answers for questions about the internet. They do this largely through relevance and then through popularity.

Question: How has this post helped you understand SEO? What other questions do you have? You can leave a comment by clicking here.

Please note: I reserve the right to delete comments that are offensive or off-topic.