What is Adsense for

Go to any webpage and chances are that you will come across ads that say "ads by google". Well these are the Adsense ads.
Adsense is a advertising program launched by Google catering mainly to the independent publishers and small business. Joining it is really simple. You sign up for the program( takes what, five mins). Your website gets reviewed. Generally within a day. Then you receive a script which you may put in any of your webpages where you want to show the ads. When viewers click on these ads, you get a percenatge of the money advertisers pay to google.

Advantages:

1. You need to apply only once. Once you are reviewed, the script you get may be added to any number of pages, even from different domains.
2. You donot have to worry about dealing with advertisers or shadowy affiliate programs. You worry about the content, Google deals with the advertisers.
3. The ads are closely matched to tyhe content of your page. So the users have links to resources they are looking for.

Disadvatages:
1. You never know what amount of money you are going to make. The information provided by Google is very vague on this count. You donot even know what percentage of money Google keeps and the percentages you get. The money per clicks varies widely from one ad to other.
2. You may get banned and Google has no liability to explain the reasons to you. People have complained of getting banned without rhyme or reason.
3. The money is paid in multiples of $100. This might be a large amount for a small website with little traffic.