Internet users are aggregated by ad exchanges (or “traffic sources”) from their origin (publisher) sites. These aggregated groups of users represent a potential audience for advertisers to target their campaigns to.
Zeustrak users target this traffic – the “audience” – and push offers to them via their campaign (URL) to gain conversions. An example of a traffic source is Facebook.
The addition of a traffic source template enables an advertiser to label each campaign based on
the specific target source, along with any additional traffic (variable) data that can be sent.
Read further: "1.2 Affiliate Network"