A fuel cell is a device that converts chemical energy from fuels, typically hydrogen, into electricity through a chemical reaction with oxygen. This process produces electricity, water, and heat, making fuel cells an efficient and clean energy source. They are used in various applications, including vehicles, stationary power generation, and portable power systems. Fuel cells operate continuously as long as they have a supply of fuel and oxygen. Unlike batteries, which store energy, fuel cells generate electricity on demand. This technology is considered a promising alternative to traditional fossil fuels, contributing to efforts in reducing greenhouse gas emissions and promoting sustainable energy solutions.