Google Adsense

Google AdSense is a new, fast and easy way for small and medium sites to make money free online by displaying relevant, text-based, un-obtrusive ads from Google AdWords (Google's own advertising program) and receiving a share of the pay-per-click payment.
Because the ads are related to what your users are looking for on your site, the results can be much better than you'd earn from banner networks and many affiliate programs.
For now, AdSense is the best way to make money free online from informational sites even if there are no obvious related affiliate programs. But you don't need to disregard affiliate programs. You can combine both these ways to make money free online and double your income.
AdSense is easy to join, it doesn't cost you anything, all you have to do is paste a few lines of code into your pages, and Google does the work of finding the best ads for them from hundreds of thousands of AdWords advertisers. You can check the relevance of the ads by looking at the text ads on the right side of this page.