Solar panels are devices that convert sunlight into electricity. They are made up of photovoltaic cells, which are made of a semiconductor material such as silicon. When sunlight hits the cells, the photons of light excite the electrons in the semiconductor material, causing them to flow, creating an electric current. This current is then collected and used to power electrical devices. Solar panels come in a variety of sizes and shapes, and can be used to power anything from a single light bulb to an entire home. Solar panels are becoming increasingly popular as a renewable energy source, as they are clean, efficient, and cost-effective.