When driving a vehicle the blind spot is the area that is around the vehicle that cannot be directly observed by the driver of the vehicle.
It's called a blind spot because you cannot easily see or cannot see at all what is around you in that blind spot.
Blind Spots exist around vehicles other than cars and exist in a wide range of vehicles such as cars, trucks, motorboats, sailboats, and aircraft.
Adding a blind spot mirror to your drivers side and passenger side mirrors can help you improve the sight in those blind spots.
The blind spot mirrors are pretty cheap and well worth it and you can just peel and stick on the blind spot mirrors.