Explain the following: Tracking Stocks

A 'Tracking stock' is a type of common stock that "tracks" or depends on the financial performance of a specific business unit or operating division of a company, rather than the operations of the company as a whole. As a result, if the unit or division performs well, the value of the tracking stocks may increase, even if the company's performance as a whole is not up to mark or satisfactory. The opposite may also be true. Tracking stock carries dividend rights tied to the performance of a targeted division without transferring ownership or control over divisional assets. In contrast to a spin-off or an equity carve-out, the parent retains full control, allowing it to enjoy any operating synergies, or economies of scale in administration or finance.