We all are living in the era of the internet that too up to the next level where each and everything has been connected to the internet. IoT has become much more popular these days with the advancement of technology and connecting physical world with the virtual world making the life of individual’s and organization easier. Recently IoT becomes more popular in the research area where many research articles have been published and reviewed. Its capacity to get associated with everything whether it's human, object, innovation, things, and so forth drawn numerous chances of advancement and extension in future. The way the technology has been evolved recently in every field we see rapid changes in the products, services, things that we are using in our daily life. IoT is platform that has becoming popular due to its simplified technology which benefits the individual’s as well as organization and end-users. Today’s IoT has given many opportunities to make easier life, effective communications and stay connected to our close and society by enabling many technologies but there are some issues which are the major concern of IoT and these issues must be resolved so that IoT can be used as revolutionary technology in future. This paper focuses on state-of–the-art porotypes on IoT, basic prerequisite in the IoT, role of big data in IoT. Enabling technologies, technology used in various applications such as smart city, agriculture, health-care, lifesaving, smart parking, urban planning. We also explore the applications of IoT and its future propensity, its architecture and comparison of IoT with H2M and M2M.