Key-word targeting gives media buyers the ability to target audiences with interests specific to the offer they, the advertiser, are promoting. 

For example, online video-gaming products find great success running on toon/hentai pages in particular, just as mature dating offers are keen to run on video pages featuring 'Milf, Mature, Cougar' etc. content.

Another Example:
Your Offer: Black Dating
Traffic: Adult tube site
Keyword targeting: Ebony, BBC, Booty

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