The Internet of Things, as defined by the Internet itself, is the connection of embedded computing devices embedded differently within the existing infrastructure. According to IoT, soon our planet will contain the largest number of devices connected to the Internet. This paper is a discussion of the trending term 'Internet of Things' challenges and opportunities, as well as the formation of IoT, which describes widely used technologies such as M2M communications, cloud computing, IPv6, and RFID technologies, thus describing the use of IoT different fields. Finally, there is a brief review of all possible IoT applications