Different from the smart grid, the Energy Internet is a unique concept comprising multiple networks, including heating networks, gas networks, information networks, and communication networks, and focused on a decentralized structure with the involvement of dominant. Different from the smart grid, the Energy Internet is a unique concept comprising multiple networks, including heating networks, gas networks, information networks, and communication networks, and focused on a decentralized structure with the involvement of dominant. Energy Internet is a concept proposed to harness, control, and manage energy resources effectively, with the help of information and communication technology. It improves a reliability of the system, and provides an increased utilization of energy resources by integrating the smart grid with the. Extensive electrification based on renewable energy sources is seen as one of the most potential growth options to tackle these issues in the medium to long term. Energy Internet (often reflects Internet plus energy) is a novel energy network that interconnects the power system components: production. This chapter presents the development of the Energy Internet throughout the history as an evolutionary solution based on modern technological development and needs, with the respect of its architecture, key features, and key concepts, such as energy router, prosumer, and virtual power plant.