Why AdSense?

While it's true that AdSense is just one advertising system, it offers a number of advantages over most of the others. Not only is there no cost to join it, it's also available to almost anyone with content on the Web. The ads are primarily text-based (image-based ads are also available as an option) and come in a wide variety of formats for placement on your pages. The ads are also drawn from the same large pool of advertisements shown by Google on its own search pages. Finally, the automated page analysis ensures that the ads displayed on your pages are relevant to the content of those pages