CPM Advertising

Sidebar Ads
by Brain, Marshall. "How Web Advertising Works." 

A sidebar ad (also known as a skyscraper ad) is similar to a banner ad, but it is ­vertically oriented rather than horizontally. Because it is vertical, the height of a sidebar ad can often reach 600 pixels or more, and sidebars are generally 120 or 160 pixels wide.
A sidebar ad has more impact than a banner ad for at least two reasons:

• A tall sidebar ad is two to three times larger than a banner ad.
• You cannot scroll a sidebar ad off the screen like you can a banner ad. With a banner ad, you can scroll just 60 pixels down and the ad is gone. With a sidebar ad, the ad is with you much longer.

Because of this increased impact, sidebar ads have higher branding power and a higher click-through rate. A typical sidebar ad has a click-through rate of 1 percent (10 clicks per 1,000