human
What are the advantages and disadvantages of having a compass in your car?
assistant
Advantages: 
1. Compasses can help you find your way when driving in unfamiliar areas.
2. They can provide information about magnetic declination, which is how much the Earth's magnetic field shifts over time.
3. Compasses can be used to measure distance, speed, and direction.Disadvantages:
1. Compasses can be difficult to read if not properly calibrated.
2. Distractions caused by using a compass while driving can increase the risk of an accident.
3. The accuracy of a compass can be affected by temperature changes, metal objects near it, and other factors.