The **rearview mirrors** are essential tools for the driver, as they allow **constant observation of the vehicle's surroundings**. These mirrors provide visibility of what is happening both behind and to the sides of the vehicle, which is crucial for safe driving.

- **Lateral and rear visibility**: The rearview mirrors help to see what is happening not only behind but also to the sides of the vehicle. This is important because, when driving, it is necessary to be aware of what is happening in all directions, not just in front.

- **Defensive driving**: It is essential to regularly check the mirrors during the journey, even if no maneuver is going to be performed. This allows the driver to be aware of their surroundings and react appropriately to any situation that may arise.

- **Blind spots**: Although the mirrors offer wide visibility, they do not eliminate blind spots, which are areas that cannot be seen through the mirrors. Therefore, it is important to turn your head and look out the window to ensure there are no vehicles in these areas before changing lanes.


In summary, the mirrors are essential for maintaining a complete view of the vehicle's surroundings, allowing the driver to make informed and safe decisions while driving.