Smart grid is a conceptual framework and interdisciplinary research domain focused on the modernization and optimization of electricity distribution networks. It investigates the integration and application of advanced information and communication technologies, sensing, and control systems to enhance grid efficiency, reliability, security, and sustainability. Key characteristics include bidirectional power flow, real-time monitoring, active management of distributed energy resources, and dynamic interaction among grid components and participants, aiming to create a more resilient, flexible, and environmentally responsible power infrastructure.