Conserving Momentum

Momentum is what keeps you moving. Like when you run downhill, you go a lot faster than if you were running ordinarily, even when it evens out you still go fast. What kept you going was momentum. By keeping running down at the mostly steady speed, you built momentum which kept you going after the hill was even. If you hit a person, you would stop and they would go forward. Why? Because you transferred our momentum to them. Same concept with the game billiards. You hit the cue ball in a manner that hits other balls into the holes. You transfer the momentum from the cue ball to the other ones. I realize this might be confusing but heres a link:http://www.grc.nasa.gov/WWW/k-12/airplane/conmo.html