A rearview mirror is a reflective device mounted inside a vehicle, allowing the driver to see the area behind the car. It helps improve safety by providing a clear view of approaching vehicles and obstacles, aiding in tasks like changing lanes and reversing. There are two main types of rearview mirrors: flat and convex. Flat mirrors offer a true-to-size reflection, while convex mirrors provide a wider field of view, making it easier to spot vehicles in blind spots. Many modern vehicles also feature adjustable mirrors and integrated technologies, such as backup cameras and blind-spot monitoring systems.