Kaep is a traditional type of double-ended Proa sailboat native to Palau.   Some of the essential design elements have also been adopted as a modern smaller multihull prototype variant. [upper-alpha 1]
The Pacific Ocean and particularly Micronesia gave birth to many different forms of simple sailing craft. Sail plan and hull form differ. Sail plans may include lateen, also known as crab-claw or half-crab-claw, Latin, or triangular. Hull formats include catamarans, doubles, proa, and singles. Presence of a beam spanning a double hull is optional. Likewise, hull end forms and shapes vary greatly. Masts for these type of sailboats can be made with one or two poles. The vessels may be made by hollowing out tree trunks, or may be assembled from planking. Other design considerations include the intended use of the vessel, for fishing, sea voyages or war, and whether they are to be used in sheltered lagoons or in the open sea. 
Additionally, there is an important and fundamental dividing line between two design types. Some vessels "shunt", that is they change course direction by using the opposite pole of a two pole mast then sailing in the opposite direction (the "Pushmi-pullyu" of the sailing world).  Others use a tacking rig, a design that is similar to sloop rigged boats found worldwide. 
Developed in Palau and used for centuries, the kaep was built from tree logs. A keel carved to a knife's edge was combined with a deep bow, giving it the ability to function in severe adverse weather, wind and waves. Sailors would crowd aft, lifting the bow out of the water, and increasing hull speed. It was used to fish, race and trade.  It is a very fast craft. 
The kaep lacks a rudder. Instead it has a "crab claw" sail,  and is further controlled by the skillful use of fore and aft trim — moving the boat's balance point, that is the center of resistance relative to the center of effort — to control her heading.   This is essentially like a wind surfer. See Sail twist.
A traditional kaep is double-ended with a reversible or pivoted (swiveling) mast, so that it can be sailed in either direction.  
A traditional kaep has an average hull 10 m (33 ft) in length, 35 cm (14 in) in width, and maximum height of 90 cm (35 in).  
The kaep has been the subject of commemorative postage stamps in Palau. 
A multihull is a boat or ship with more than one hull, whereas a vessel with a single hull is a monohull. The most common multihulls are catamarans, and trimarans. There are other types, with four or more hulls, but such examples are very rare and tend to be specialised for particular functions.
A sailing ship is a sea-going vessel that uses sails mounted on masts to harness the power of wind and propel the vessel. There is a variety of sail plans that propel sailing ships, employing square-rigged or fore-and-aft sails. Some ships carry square sails on each mast—the brig and full-rigged ship, said to be "ship-rigged" when there are three or more masts. Others carry only fore-and-aft sails on each mast, for instance some schooners. Still others employ a combination of square and fore-and-aft sails, including the barque, barquentine, and brigantine.
A sailboat or sailing boat is a boat propelled partly or entirely by sails and is smaller than a sailing ship. Distinctions in what constitutes a sailing boat and ship vary by region and maritime culture.
A sail plan is a description of the specific ways that a sailing craft is rigged. Also, the term "sail plan" is a graphic depiction of the arrangement of the sails for a given sailing craft.
A catamaran is a multi-hulled watercraft featuring two parallel hulls of equal size. It is a geometry-stabilized craft, deriving its stability from its wide beam, rather than from a ballasted keel as with a monohull boat. Catamarans typically have less hull volume, smaller displacement, and shallower draft (draught) than monohulls of comparable length. The two hulls combined also often have a smaller hydrodynamic resistance than comparable monohulls, requiring less propulsive power from either sails or motors. The catamaran's wider stance on the water can reduce both heeling and wave-induced motion, as compared with a monohull, and can give reduced wakes.
A trimaran is a multihull boat that comprises a main hull and two smaller outrigger hulls which are attached to the main hull with lateral beams. Most modern trimarans are sailing yachts designed for recreation or racing; others are ferries or warships. They originated from the traditional double-outrigger hulls of the Austronesian cultures of Maritime Southeast Asia; particularly in the Philippines and Eastern Indonesia, where it remains the dominant hull design of traditional fishing boats. Double-outriggers are derived from the older catamaran and single-outrigger boat designs.
An outrigger is a projecting structure on a boat, with specific meaning depending on types of vessel. Outriggers may also refer to legs on a wheeled vehicle that are folded out when it needs stabilization, for example on a crane that lifts heavy loads.
Outrigger boats are various watercraft featuring one or more lateral support floats known as outriggers, which are fastened to one or both sides of the main hull. They can range from small dugout canoes to large plank-built vessels. Outrigger boats can also vary in their configuration, from the ancestral double-hull configuration (catamarans), to single-outrigger vessels prevalent in the Pacific Islands and Madagascar, to the double-outrigger vessels (trimarans) prevalent in Island Southeast Asia. They are traditionally fitted with Austronesian sails, like the crab claw sails and tanja sails, but in modern times are often fitted with petrol engines.
Proas are various types of multi-hull outrigger sailboats of the Austronesian peoples. The terms were used for native Austronesian ships in European records during the Colonial era indiscriminately, and thus can confusingly refer to the double-ended single-outrigger boats of Oceania, the double-outrigger boats of Island Southeast Asia, and sometimes ships with no outriggers or sails at all.
Tacking is a sailing maneuver by which a sailing vessel, whose desired course is into the wind, turns its bow toward and through the wind so that the direction from which the wind blows changes from one side of the boat to the other, allowing progress in the desired direction. The opposite maneuver to tacking is called 'jibe', or 'wearing' on square-rigged ships, that is, turning the stern through the wind. No sailing vessel can move directly upwind, though that may be the desired direction, making this an essential maneuver of a sailing ship. A series of tacking moves, in a zig-zag fashion, is called beating, and allows sailing in the desired direction.
A tepukei, tepuke or TePuke is a Polynesian boat type, characterized by its elaborate decking, its submerged hulls and symmetrical "crab claw" sail slender foil or radically extended tips claw sail. Tepukei boats are produced primarily by the Polynesian-speaking inhabitants of Taumako, and have been occasionally borrowed by other Polynesian and Melanesian societies.
Canoe sailing refers to the practice of fitting an Austronesian outrigger or Western canoe with sails.
The crab claw sail is a fore-and-aft triangular sail with spars along upper and lower edges. The crab claw sail was first developed by the Austronesian peoples some time around 1500 BC. It is used in many traditional Austronesian cultures in Island Southeast Asia, Micronesia, Island Melanesia, Polynesia, and Madagascar. Due to its extraordinary performance and ease of operation, it has also become very popular in modern sport sailing. It is sometimes known as the Oceanic lateen or the Oceanic sprit, even though it is not restricted to Oceania, is neither a lateen sail nor a spritsail, and has an independent older origin.
A mast-aft rig is a sailboat sail-plan that uses a single mast set in the aft half of the hull. The mast supports fore-sails that may consist of a single jib, multiple staysails, or a crab claw sail. The mainsail is either small or completely absent. Mast-aft rigs are uncommon, but are found on a few custom, and production sailboats.
The Hilu outrigger is a personal size, beach launched sports boat in the sailing canoe style. Hilu was AMF's production version of a boat variety more commonly found in designs hand built by outrigger aficionados. Hilu utilizes fiberglass pontoons and carries a single polyester lateen sail mounted to an un-stayed aluminum mast.
Paraw are various double outrigger sail boats in the Philippines. It is a general term and thus can refer to a range of ship types, from small fishing canoes to large merchant lashed-lug plank boats with two outriggers (katig) propelled by sails
A sail is a tensile structure—made from fabric or other membrane materials—that uses wind power to propel sailing craft, including sailing ships, sailboats, windsurfers, ice boats, and even sail-powered land vehicles. Sails may be made from a combination of woven materials—including canvas or polyester cloth, laminated membranes or bonded filaments—usually in a three- or four-sided shape.
The following outline is provided as an overview of and topical guide to sailing:
Polynesian multihull terminology, such as "ama", "aka" and "vaka" are multihull terms that have been widely adopted beyond the South Pacific where these terms originated. This Polynesian terminology is in common use in the Americas and the Pacific but is almost unknown in Europe, where the Anglo-Saxon terms "hull" and "outrigger" form normal parlance. Outriggers, catamarans, and outrigger boats are a common heritage of all Austronesian peoples and predate the Micronesian and Polynesian expansion into the Pacific. They are also the dominant forms of traditional ships in Island Southeast Asian and Malagasy Austronesian cultures, where local terms are used.
Sakman, better known in western sources as flying proas, are traditional sailing outrigger boats of the Chamorro people of the Northern Marianas. They are characterized by a single outrigger and a crab claw sail. They are the largest native sailing ships (ladjak) of the Chamorro people. Followed by the slightly smaller lelek and the medium-sized duding. They are similar to other traditional sailing ships of Micronesia, like the wa, baurua, and the walap. These ships were once used for trade and transportation between islands.
The Kaep is a high performance ultra light proa fitted with an easily manageable windsurf rig of 5 sq. mtr.