The so called internet of things (IoT) is a form of technology advancement that has a capacity for driving change in our daily lives in a variety of sectors. The fantastic opportunity will help in the collection of data that is relatively exponential and in a manner that is continuous to present changes that are significant on the lives. Devices growth and the speed in which they are developed to attain the IoT era of technology offers the challenges of security and the battling of freedom as people establish policies and governance that rebuilds the developments without interfering with the innovations. Among the issues, includes the concerns on the security and privacy brought by the technology. The vulnerabilities of security that are experienced by the IoT devices are as a result of the contributing factors like the low capabilities of the devices in terms of energy and the capabilities of computing, the wireless channels are seemingly unreliable, and the vulnerabilities on the physical nature of the devices. This paper will focus on the IoT evolution, the definitions attached to IoT, and some of the many applications of IoT. It will create an emphasis on the considerations of security and privacy, including the challenges that are tied to the general IoT and the IoT application context. A critical assessment of the works done for IoT is presented by the literature review on the perspective of the developmental era and the evaluation of the trend. The paper will also give the IoT security risks taxonomy, mechanisms, and attacks related to the technology.