The advancement of digital technologies has become a pivotal factor in the transformation of local energy systems. As we strive towards creating sustainable, reliable, and efficient energy networks, the adoption of cutting-edge technologies like smart grids, blockchain, Internet of Things (IoT), digital twins, cybersecurity measures, and artificial intelligence (AI) with machine learning (ML) capabilities, is reshaping how energy is produced, distributed, and consumed. This chapter briefly introduces each of these technologies, exploring their roles and implications within the context of local energy systems. The details of each technologies and their applications will be discussed in the following chapters of this book.