Publishers are the producers of sites that display digital content for the consumer audience. Advertiser products or services are promoted on publisher sites.
Publisher notifications about installs and/or other events.
A server postback is a URL request to a third-party system that notifies them of a conversion (typically an install). You can set up postback URLs for each publisher on all mobile apps (a global postback URL) or you can add the postback URL for a single mobile app.