Google AdSense is a program run by Google Inc. that allows publishers in the Google Network of content sites to serve automatic text, image, video, and rich media adverts that are targeted to site content and audience. These adverts are administered, sorted, and maintained by Google, and they can generate revenue on either a per-click or per-impression basis. Google beta-tested a cost-per-action service, but discontinued it in October 2008 in favor of a DoubleClick offering (also owned by Google). In Q1 2011, Google earned US$2.43 billion ($9.71 billion annualized), or 28% of total revenue, through Google AdSense.

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In May 2005, Google announced a limited-participation beta version of AdSense for Feeds, a version of AdSense that runs on RSS and Atom feeds that have more than 100 active subscribers. According to the Official Google Blog, "advertisers have their ads placed in the most appropriate feed articles; publishers are paid for their original content; readers see relevant advertising—and in the long run, more quality feeds to choose from."

AdSense for Feeds works by inserting images into a feed. When the image is displayed by a RSS reader or Web browser, Google writes the advertising content into the image that it returns. The advertisement content is chosen based on the content of the feed surrounding the image. When the user clicks the image, he or she is redirected to the advertiser's website in the same way as regular AdSense advertisements.

AdSense for Feeds remained in its beta state until August 15, 2008, when it became available to all AdSense users.