A photovoltaic cell is a device that converts sunlight directly into electricity. It works by using materials that exhibit the photovoltaic effect, where light energy knocks electrons loose, creating an electric current. These cells are commonly made from silicon and are a key component of solar panels. Photovoltaic cells are widely used in various applications, from powering small devices like calculators to providing electricity for homes and businesses. They are an essential part of renewable energy systems, contributing to the reduction of greenhouse gas emissions and reliance on fossil fuels, thus promoting a more sustainable future.