Google's computers do, however, scan Gmail messages to place contextual ads next to the emails themselves.

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Mobile, social, location, sensor and big data technologies have made the possibility of truly contextual ads a reality.

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When Google began displaying contextual ads inside Gmail based on the content of each e-mail, the move generated lots of attention.

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Bing Network Contextual Ads, will allow websites to run text ads (like those pictured on the top right) from the Yahoo!

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Some times contextual ads take on a comical texture.

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The company initially began hosting contextual ads on the blogs but has since cut those out, leaving ads only on the sites of bloggers who want to be AdSense partners and share in profits.

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The most prevalent ads throughout the company's beta test were short video spots from Esurance, but the network will also provide contextual and text ads.

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We would likely love ads and offers if they were truly contextual.

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Display ads are generally targeted towards users based on their current context (contextual targeting), past behavior (behavioral targeting), or a combination of the two.

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