I have been lookng at Yatchs online and they all quote dimentions etc, but im not sure exactly what they mean by height, do they mean...

1) Height from deck to top of sail

2) Height from water line to top of sail

3) Distance from bottom of keel to top of sail.


...is the definition always the same or do I have to be careful about how 'height' is measured?


Thanks

David Bevan