Part II – How Google AdSense works

Please keep in mind, this is a very basic description of how the Google AdSense for Content product works.  I have not implemented the other advertising tools, yet and there is a limit to what I can and cannot say about the service.  Here’s what I can tell you..

Google’s Content Search Index

Google is a search engine, so they have software running at their offices that searches everything it can find on the Internet.  Google’s  indexing engine, starts with a set of web pages it knows about and follows all the links it finds until it runs out of links.  The indexing engine creates an index of words and phrases contained in each web page it finds.  From this, Google can get a rough idea what the content is on a given web page.

Google’s AdSense for Content

Next, you go to Google’s AdSense for Content site and use the tool there to generate an ad placement. The tool produces JavaScript code that you can cut from Google’s web page and paste into your own HTML code wherever you choose to place an ad.  The JavaScript retrieves a new ad every time your web page is loaded.  Google decides when and how to rotate the ads in your web page.

When a visitor to your site reads the web page containing the Google JavaScript, their browser connects to Google, downloads and displays the ad content.  This technology works fine, provided:

  1. The viewer hasn’t disabled JavaScript in their browser.
  2. The reader isn’t using some sort of ad-blocking tool such as the AdBlock Plus plugin for Mozilla.

These two factors limit the number of “ad impressions” your site can actually deliver, lowering your site’s value to the advertiser.  This, in turn, limits the revenue you can generate from advertising.  Now that I’m the one implementing ads, I see the AdBlock plugin I use in Firefox a bit differently–but not enough to stop using it.  Google has acquired Doubleclick and Doubleclick uses various techniques including web bugs, cookies and other technologies to track anyone who has ever viewed a Google-placed ad.  This is great for Google, Doubleclick and the advertisers, but terrible for the rest of us and our privacy.

Generating Earnings

Google claims you make money when ads are displayed and when ads are clicked on. This did not prove to be true for me. I only made money when ads were clicked.

Part III  of this series will showcase my experiences during my first month using the Google AdSense product.