It is O.K. to be confused here because this is a poor place to learn the rules. (Most of) The guys explaining are doing a good job but they are only doing word descriptions - no drawings even; no video, no other visual aids. Makes for a tough teaching environment. There are plenty of other websites that will provide those other tools to make learning much easier. Take your curiosity to those places and learn before you get too frustrated and give up. It will soon make sense when you can see it applied. Here is one example: http://raceadmin.ussailing.org/Rules/Animated_Handy_Guide.htm?bcpid=61494017001&bckey=AQ~~,AAAADkpfq7E~,4OewegLUcjErjwxev9HJ8XQuMzR8VOpx&bclid=110123965001&bctid=111698220001