A tracker is a way to tag your campaigns, traffic sources, ad spots, and banner names. A tracker helps you pinpoint how many hits are coming from a particular source and how many sales are being generated.
Trackers are data… and data is information.
The information contained within a tracker should be relevant to your campaigns.
Trackers can be thought of as little memory cues that can help jog your memory on what you’ve done (that turned out to be successful), or that provide you with great insight of your success.
Read more here: