In a car crash with a pedestrian, or bicyclist, the law of gross tonnage applies. The law of gross tonnage states that when two bodies impact, the body with the larger gross tonnage will fare better in the collision that the body with the lighter gross tonnage. In any collision between a car and a pedestrian, or a bicyclist, the car will always fair better.
Generally, the pedestrian or the cyclist will suffer serious personal injury, such as a brain injury, a spinal cord injury, or amputation, or even wrongful death. A secondary effect of such a collision, as I tell my children when they see a child or other pedestrian using the road, is the guilt that will follow the driver, likely for the rest of their lives.
To avoid these collisions take a few precautions.
In a residential area, make sure you have your vehicle under control and that you are traveling at a speed which will allow you to stop quickly, especially if you see children present.
Treat children like a stop sign. Children are unpredictable by nature, treating them like stop signs means that regardless of what they do, you will not hit them.
Drive with your lights on no matter the time of day. In the daytime, your lights are an added advantage to being seen by pedestrians. In the night your lights serve as both a beacon to the pedestrian, and allows you to see.
Do not out drive your lights. Your lights, at night, only project so far. In an urban area, travelling at a high rate of speed may cause your lights to be ineffective at allowing you to see far enough ahead to be able to stop or react quickly.
Never drink and drive. Call a cab. Give a friend your keys. Walk. Just do not drink and drive.
Be careful, not only for the sake of the pedestrian and the cyclist, but for your own peace of mind.