Electrical grid is a complex system designed to deliver electricity from generation to consumers. The constantly changing energy consumption requirements, along with the technological evolution pave the way for the upgrading of the electrical grid. Internet of Things (IoT) increases the automation and intelligence of devices, reducing the need for human interaction. Moreover, Industrial Internet of Things (IIoT) describes IoT applications in industrial systems. IIoT consists of a great number of low-cost interconnected devices, including sensors, actuators, and programmable logic controller (PLC). Such environments deal with vast amounts of data originating from a wide range of devices, applications, and services. The incorporation of IIoT to the electrical grid drives to the rise of the smart grid. In this chapter we provide an analysis of the smart grid architecture, its core components, and related technologies. Furthermore, we introduce information flow control and analyze several use cases that describe different business scenarios in smart grid environments. Finally, we discuss the current challenges regarding the security of smart grids.