A ketch is a sailing craft with two masts. The distinguishing characteristic of a ketch is that the forward of the two masts (the "mainmast") is larger than the after mast (the "mizzen"). Historically the ketch was a square-rigged vessel, most commonly used as a freighter or fishing boat in northern Europe, particularly in the Baltic and North seas. In modern usage, the ketch is a fore-and-aft rigged vessel used as a yacht or pleasure craft.