A wristband is a flexible band worn around the wrist, often made from materials like fabric, silicone, or plastic. They can serve various purposes, including identification, fashion, or promotional use. For example, event organizers often distribute wristbands to attendees for access control at concerts or festivals. Wristbands can also be used for health monitoring, such as fitness trackers that measure heart rate and activity levels. Some wristbands are designed for medical purposes, like alerting others to a person's allergies or medical conditions. Overall, wristbands are versatile accessories with practical applications in everyday life.