A catamaran is a watercraft with two parallel hulls of equal size. The wide distance between a catamaran's hulls imparts stability through resistance to rolling and overturning; no ballast is required
The Spirit of Dallas catamaran on White Rock Lake
A Formula 16 beachable catamaran
Powered catamaran passenger ferry at Salem, Massachusetts, United States
1827 depiction of Tahitian pahi war-canoes
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
Catamaran
…single outrigger canoe, then to the reversible single outrigger canoe. Finally, the single outrigger types developed into the double outrigger canoe (or trimarans). This would also explain why older Austronesian populations in Island Southeast Asia tend to favor double outrigger canoes, as it keeps the boats…
USA-17—a 90-foot-long (27 m) trimaran, type BOR90.
A traditional paraw double-outrigger sailboat (bangka) from the Philippines
An Iranun lanong, a double-outrigger warship from the Philippines used in the navies of the Sultanates of Maguindanao and Sulu from the 18th to late 19th centuries. They were also commonly used for raids and piracy.
The Balatik, a paraw, a functioning replica of a traditional Austronesian sailing trimaran from the Visayas Islands of the Philippines