With digital TV switchover and using cognitive radio technology, a spectrum of unoccupied TV channels, called TV white spaces (TVWS), can be used for different applications. Radio signals in these bands travel farther and penetrate obstacles more effectively than those in cellular and 2.4 GHz band owing to the lower frequency. With the growth in wireless services and higher data rate applications, the demand for spectrum is also increasing. Studies show that such licensed spectrum is underutilized. This chapter covers the study on TVWS, its architecture, and protocols, TVWS over low-power wide-area networks, along with its applications and future challenges and opportunities.