The difference between TDR and FSI is that Transfer of Development Rights allows the transfer of unused Floor Space Index from one plot to another, providing flexibility in urban development and enabling higher density in some areas without breaching overall FSI limits. If the municipal corporation acquires land or properties for city development, it may issue TDR certificates to owners in lieu of cash. These owners may then sell this TDR to developers, who need it for constructing more floors in their developments.