Power management refers to the process of monitoring and controlling the distribution and consumption of electrical energy in devices and systems. It aims to optimize energy use, reduce waste, and extend the lifespan of equipment. This is particularly important in devices like computers and smartphones, where efficient power management can lead to longer battery life and improved performance. In larger systems, such as data centers or smart grids, power management involves coordinating multiple energy sources and loads to ensure reliability and efficiency. Techniques include load balancing, energy storage, and the use of renewable energy sources, all of which contribute to a more sustainable and cost-effective energy system.