You've probably heard a lot about Google AdSense, but you may not know just what it is. Well, for one thing, it's a one of the hottest new ways to make money online without having to do a whole lot. If you have read Robert Kiyosaki's book, "Rich Dad, Poor Dad", you know that passive income is the best kind of income to have.

You'll have to invest just a little bit of time in learning about it, but once you get it set up you can look forward to seeing those nice checks roll in. Or, if you're totally online, seeing money flow into your PayPal account.

Google AdSense is a fast and absolutely ridiculously easy way for people with websites of all types and sizes to put up and display relevant Google ads on the content pages of their site and earn money.

So what kind of ads do you have to put up? That's the good part. You don't have to decide. Google does it for you. AdSense always delivers relevant ads that are precisely targeted on a page-by-page basis to the content that people find on your site. For example, if you have a page that tells the story of your pet fish, Google will send you ads for that site that are for pet stores, fish food, fish bowls, aquariums. You get the picture.

Here's the thing you need to know: Google has no strict criteria for acceptance into the AdSense program, and Ad Sense doesn't hit you with a minimum traffic requirement. The only criteria they're really sticky about is the standard "acceptable content" requirements, and that's pretty standard almost anywhere.

Once you've been accepted into Google AdSense, you'll be able to get the AdSense advertisements on any site you own using the same ad code, provided you obey the Google guidelines. (And that's very, very important more on that later.)

It's easy to get started with AdSense and it only takes a few minutes. You fill out one single online application and that's it. Once you're approved, it takes only minutes to set up AdSense; all you have to do is copy and paste a designated block of HTML into the source code for your site. Once you do that, targeted ads will start showing up on your website and start watching those nice checks roll in.

While I can't guarantee results, of course, since a lot of your success lies in your own hands, I wouldn't have written this article if I didn't believe in the power of Google AdSense. A lot of webmasters are making a lot of money off of AdSense, and there's no reason you shouldn't be one of them.

To date, comparisons of AdWords rates with Ad Sense earnings add up to commissions of between 40% and 60%. People speculate all the time on user boards as to why Google refuses to publish its commission rates, but no one has the answer. It might have something to do with legal reasons or it could just be that Google wants to retain the ability to change rates without having to send out an announcement about it each time, which costs money.