Voluntarily taking such a course may reduce insurance premiums -- ask your insurance company. I took one last summer, after getting a speeding ticket. It reminded me a lot of the driving class I took in high school, almost like a refresher, and most of it was common sense. As much as I'd like to believe the problem is with people not following defensive driving rules, the fact that many of my classmates couldn't figure out the correct answer was really unsettling.
Defensive driving is supposed to be an attitude. It consists of habitually following guidelines. The method deals mostly with two concerns:
1) you can get into an accident
2) other drivers can make mistakes.
Because of this, a driver needs to be aware of potential dangers and be able to effectively react to actual dangers. This does not mean slow or timid driving. It requires a lot of paying attention and reacting to what is going on around you.
There are some core concepts, including:
being prepared and looking ahead
This consists of a technique called scanning. You should look far ahead enough to allow you enough time to stop your vehicle by the time you reach that point. How far you scan depends on your speed and your environment (city, rural). Scanning includes not only looking for actual dangers, but for potential dangers as well. If dangers are spotted, speed should be decreased to allow yourself more time to brake, as well as notifying drivers behind you that you may need to brake suddenly.
Watch out for other drivers. Do not assume they will stop if there is a stoplight or sign. The person stops the car, not the light. People make mistakes. When approaching tollbooths, be very cautious, as drivers frequently change lanes at the last second. Even if you have the right of way, you must be given the right of way by other drivers.
Treat parking lots as if they were roads. Do not cut across parking spaces, use the aisles as roads. Stop at intersections. Beware of drivers cutting through spaces. Be cautious of pedestrians.
Know what is around you at all times. Check the rearview and sideviews frequently. Don't forget to check blindspots.
Your speed is regulated not only by the posted speed limit, but by conditions. This does not include just the weather, but other things such as heavy traffic and construction work. Adjust your speed by common sense.
Reduce speed before entering a curve. Braking in the curve has a greater chance of inducing a skid.
4 out of 10 accidents involve rear-end collisions.
Maintain a safe following distance from the car in front of you. Follow the 2 second rule - give yourself 2 seconds of space. This needs to be adjusted with conditions, 3-4 seconds and up. You can figure out the distance by using a fixed marker (such as a sign or an overpass). Adjust your distance so that when you finish counting, you will have reached the fixed marker.
Try not to be boxed in by vehicles to your sides. You want an escape route if the need arises.
When coming to a stop, stop so you can see the bottom of the rear tires of the vehicle in front of you. This is because:
if you are rear-ended, you will be less likely to rear-end the car in front of you
if the car in front stalls, you can go around it without backing up
you will not be boxed in if someone threatening approaches your car
if you are on a hill, you have room if the car in front rolls back
there is more room for error when braking
Always wear a seatbelt. Wear it correctly. Wear the shoulderbelt.
Avoid putting children in the front. Never put a child safety seat in the front.
your physical condition
If you are incapable of driving, do not do so. This includes drowsiness.
Keep your window rolled all the way down or most of the way up. In side-impact collisions, there is a greater chance of injury if the window is rolled halfway (at head height).
Ignore drivers who cut you off. Nothing can be gained by tailgating them.