Photovoltaic devices are technologies that convert solar energy into electricity. These devices typically consist of solar cells made from materials such as silicon, cadmium telluride, or copper indium gallium selenide. When sunlight hits the solar cell, it creates an electric current through the photovoltaic effect. Photovoltaic devices are used in a variety of applications, including rooftop solar panels, solar farms, and portable chargers. They are a key technology in the transition to renewable energy sources and have the potential to significantly reduce greenhouse gas emissions and dependence on fossil fuels.