This article will explain the four major parts of a sloop-rigged (one mast, two sails) sailboat and how they work in a non-technical fashion.

Sails: When adjusted (trimmed) properly, the two sails (the mainsail and the jib or headsail) on a boat are said to be "balanced" and work together to propel the boat forward. However, each sail by itself is also working to turn the boat relative to the wind. The mainsail turns the boat toward the wind (windward, or "to weather") and the headsail turns the boat away from the wind (leeward).

Keel: Beneath the boat, the keel's mass not only helps keep the boat upright, it also acts like an underwater wing to help keep the boat moving forward after the sails have been used to get the boat up to speed. The keel is said to provide "lateral stability" because without it, the force of the wind would force the boat to move sideways. Boats that do not have keels generally have a centerboard that can be raised and lowered. Although this allows the boat to be brought up on to shore easily, these types of boats do have more sideways motion.

When docking or leaving a dock under sail power only, the mass of the keel must be taken into consideration and overcome through the proper use of the sails and steerage of the boat (see my other hubs).

Hull: The hull or body of a sailboat affects performance based on its shape. Keelboats tend to have hulls that are about 3-4x their width, while centerboard boats are generally twice as long as their width.  The extra width or "beam" of a centerboard boat is used in place of a keel to provide buoyancy and keep the boat upright.

Rudder: The rudder, like the keel, is beneath the boat, and is controlled with a wheel or a long, narrow tiller. Although its effect is to turn the boat, the rudder actually blocks the flow of water on one side of the boat. At low wind speeds or with a heavier boat, turning the rudder too far will actually slow the boat down and work against the action of the sails.