What is the specific name for the advertising displayed in "text links"?

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Yes, I know you'll come in here thinking one thing but I mean something totally different then you were thinking. Wasn't sure how else to explain it, though. However. Mylot seems to use it where every now and then a word turns blue in something someone says and you hover over it and an AD is displayed. Was just curious if there is a specific name for what this type of advertising is called and if you know of any companies that do this kind of advertising and pay for it, and preferably pay to paypal, but I guess check-paying sites would work too. Thanks for the help!