Bells are musical instruments that produce sound when struck. They come in various shapes and sizes, from small hand bells to large church bells. Often made of metal, bells can be found in many places, such as schools, churches, and town squares. They are used to signal time, celebrate events, or call people together. The sound of a bell is created by vibrations, which travel through the air and reach our ears. Different bells have unique tones depending on their size and material. For example, a school bell might ring to signal the end of a class, while a wedding bell often symbolizes joy and celebration.