Capping (also called frequency capping) is a setting that allows limiting the maximum number of impressions/views a visitor can see a specific ad within a certain time period.
Publisher runs a http://www.example.com/. This publisher has decided to show Adcash campaigns and has created Pop-Under zone and one footer. As the publisher placed the Pop-Under script on the landing page (the first page), then every time a visitor comes to the page and clicks somewhere the Pop-Under opens. As the publisher didn't want to interrupt their audience with too many ads, they decided to show one Pop-Under ad to each user once a day. It can be set from 30 minutes to 24 hours etc. If the publisher wouldn't use capping then the Pop-Under would be opening with every single click that the visitor does.
How to set up capping
Go to Zones tab in publisher's panel.
Find the zone you want to set up capping for and drop down its settings.
Find the settings box where you can input the number of impressions for several pre-defined time periods including 30 min, 1h, 4h, 8h, 12h, 24h.
In the example above, one user will be shown this specific advertisement once in twenty-four (24) hours.
Adcash always recommends capping, since it helps to get better eCPM results and won't disturb the user experience.