You have many options when you’re running ads from an ad network on your site. You can run straight-up banner ads, of course, but you may choose to include pop-up ads, pop-unders, and in-text ads.
Pop-ups and pop-unders are pretty universally reviled, and most publishers opt out of this kind of ad delivery instinctively. After all, we don’t like visiting sites with those kinds of ads, so we don’t want to force that on out readers.
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