SA WIKIPEDIA-E
http://en.wikipedia.org/wiki/E-mail_tracking
Some e-mail marketing tools include tracking as a feature. Such e-mail tracking is usually accomplished using standard web tracking devices known as cookies and web beacons. When you send a tracked e-mail message, if it's a graphical HTML message (not a plain text message) the e-mail marketing system may embed a tiny, invisible tracking image (a single-pixel gif, sometimes called a web beacon) within the content of the message. When the recipient opens the message, the tracking image is referenced. When they click a link or open an attachment, another tracking code is activated. In each case a separate tracking event is recorded by the system. These response events accumulate over time in a database, enabled the e-mail marketing software to report metrics such as open-rate and click-through rates. E-mail marketing users can view reports on both aggregate response statistics and individual response over time.
znaci da ipak postoji tracking, ali samo ukoliko se na neki nacin aktivira u datom mail-u?