Abstract
New technologies like the Internet of Things (IoT), Smart City (SC), and Big data have changed the way we look towards life. These technologies created integration between the physical and virtual world that paved the way for many services that we could not imagine a decade ago for the users. The fuel for these services is the sensed data, which can be collected anytime and anywhere by using sensors. However, these technologies and their services have several challenges on their way ahead. This will decide how they will evolve in the future. The most sensitive and critical challenges are security and privacy of user's data. Unfortunately, there is no real comprehensive understanding of the two concepts so far. This paper highlights both concepts, definitions, points of interests in each one, distinguishing aspects and compatibility. In addition, few practical cases are discussed with a focus on security and privacy for the IoT environment.