Abstract. The Industrial Internet of things is getting more attention nowadays both from academia and industry. IoT would help in connecting objects to the internet. Here the object may mean differently in different domains. In the context of the manufacturing domain, the Industrial Internet of things (IIoT) would help in connecting all elements including different types of machine tools and material handling equipment used in the manufacturing of a product. IIoT may be defined as a set of interconnected intelligent machines with reduced operational cost and capable of monitoring on their own. IIoT is also known by other names such as Industry 4.0, Industrial IoT, and Smart manufacturing. IIoT not only would help in connecting machines through the wireless network but also enable machine-machine communication with minimum human intervention. IIoT would make use of sensors for collecting data about product manufacturing. IIoT is capable of handling modern-day complex business processes. Industrial Internet (IIoT) provides better visibility in terms of understanding operations of the company by making use of sensors, hardware, software and cloud. Improved decisions are possible using IIoT, hence many industries have started implementing IIoT. The main contribution of this article is to review existing literature, identify gaps and provide direction for further research.