For standard ad zones, Advertisement Count is a setting that controls how many ads appear in that zone on a single page load. By default, the Advertisement Count is set to a value of 1.
Displaying One Ad Per Zone Per Page Load:
Let’s say you had 3 ads targeted to run in a zone. With an Advertisement Count of 1, only one ad would appear in that zone. On subsequent page views, one of the 3 targeted ads will be randomly chosen and displayed. This is the most common behavior that publishers used.
Displaying Multiple Ads Per Zone Per Page Load:
If you set the Advertisement Count to 2, two of the three ads would be randomly chosen to display in that zone. The adserver will display the ads immediately following each other, so you may want to additionally set the Style option in Advanced Settings on the same page (scroll down to view).
Separating Multiple Ads with a Margin:
You can separate multiple ads by a thin margin by adding a margin setting similar to the following in the Style option:
display: block; margin-bottom: 10px;
Advertisement Count vs. Separate Zones:
You can also display multiple advertisements on a page by adding separate zones for each, but using the Advertisement Count makes the adserving much more efficient.
Some publishers, like The Batavian, have many, many ads down the sidebar of the page. Instead of having 100+ zones on a single page, they have a few zones, each of which displays 10-20 advertisements. Instead of making 100+ zone calls on a single page, there are only 5 to 10. However, this option is only recommended if you have many back-to-back ads displaying.
Special Note for Rotating (Slideshow) Ad Zones:
If the zone in question is a rotating/slideshow-style zone, the Advertisement Count will control how many ads or slides appear in the zone. If you have 10 advertisements book in a zone, but the Advertisement Count of that zone is 5, only 5 randomly chosen ads will be selected from the group of 10 and displayed in that zone.