Headlights can be
visible for over a mile, but may only illuminate a less
then a couple hundred feet. Just because you can see an
approaching vehicle doesn't mean they can see your vehicle.
When pulling out of a driveway, be sure there is adequate
time for you to get up to speed and into your lane before
traffic has to brake or take evasive action to avoid colliding
with you. This animation demonstrates how much more time
a driver has to percive the other when he has a good view
of approaching headlights, but the other driver doesn't.