When sailing with Grandpa something magical always happens. You can't sail without wind. Grandpa's sailboat is called a sloop and has two sails. It also has a little engine just in case there is no wind. The big sail is called the main sail and the smaller sail is called the jib. When it is very windy the boat can sail with just the jib, so it does not tip to the side too much. It's really funny; there is a boat language.