To drive in a **comfortable and safe** manner, it is essential to correctly adjust the seat, the backrest, and the **headrest**. The headrest should be at the height of your head to provide adequate support and prevent injuries in the event of an accident. This is important for all vehicles, not just passenger cars.

- **Adjustable headrest**: It is crucial that the headrest is adjustable to fit the driver's height. This ensures that the head is well supported and reduces the risk of cervical injuries in the event of a collision.

- **Proper posture**: A good driving posture, with the headrest correctly adjusted, helps to avoid fatigue and improves the ability to respond to unforeseen events. This is crucial for maintaining driving safety.

Therefore, headrests should always be adjustable to ensure the driver's safety and comfort in any type of vehicle.