Rear end collisions occur when a vehicle hits the one in front from behind. They can happen due to inattentive driving, tailgating, sudden stops, or poor road conditions. In a rear end collision, the following vehicle will experience the same force as hitting a stationary object at half the speed. Common injuries from moderate speed rear end collisions include whiplash, while more serious accidents can cause extensive injuries or death, especially for rear passengers. The driver of the vehicle that caused the collision is typically at fault except in rare cases like if the front vehicle was in reverse.