An affiliate program is...

...a service which give you money when the visitors of your website(s) click on some sponsored links. (advertising)

 Adsense is the affiliiation program made by google and it's a "pay by click" program: this means that you are rewarded when they click on the advertising sent by google. All the procedure is automatic, google analyze your pages and shows related advertising.

 If you talk about spiritual issues google will probably send advertising related to bible vendors. But this is only theory, because sometimes the engine screw things up entirely.

Well, google adsense remains one of the easiest ways to monetize websites: You ask to be a member of adsense, submit your pages and if accepted google allow you to publish a special javascript code that does the magic.

Even if you're not a technical person, the adsense control panel is clean and efficient: you can adjust size and number of the "ads" that will be show on your pages, the colors, etc and you have access to a good numer of reports.


Ok but... where does the money come from?

Good question: google has a twin system that collect the advertising requests (and money) from people that like to have some extra visits. That's Google Adwords.

Adwords users pay each click a certain amount of money (from 0.05 dollars to sometimes 2-3 dollars a click and in rare cases even more). Google pays a part of this cost to the adsense users and keep some profit for itself.  

During the heydays of the adsense, this mechanims was so well oiled that some people earned a good amount of money simply referring people to "fake" sites, made for adsense.

Then the fake clickers appeared: people started creating scripts to simulate clicks and when google become aggressive about that, people raised "clicking brigades": lots and lots of cheap web users from third world countries. 

In the end the "trust" of the adwors users towards the majority of sites was decreased and the sums of money involved dropped accordingly. Nowadays a serious adwords users would not be money on the so-called "content network" but only on the google search results pages and the closely-guarded partner-sites. (i know because me and my coillegues disable the content network).

There are some alternatives to adsense and we will examine them. Younger but mor e aggressive companes, that try hard to cut their own slice of the advertising cake!