Mega Yachts are over 30 meters (100 feet) and professionally crewed; it may be also a luxury or super yacht. It may be either a sailing yacht or motor yacht.

History: the term Mega Yacht and Luxury Yacht have been present since the last 20th century when the rich made big personal yachts for enjoyment. For instance, Cox & King yachts, motor yachts Christiana O and Savarona are the early luxury motor ones. Americas Cup classic J class racers such as S/Y endeavour and Sir Thomas Lipton's Shamrock are the early Mega Yachts. In the Gilded Age, the New York Yacht club hosted many luxury sailing yacht events at Newport, Rhode Island.

Today: the number and popularity of big personal Mega yachts have developed up over the last few years. Luxury or Mega Yachts do not have real homeports though the owners have to register in a port of the country whose flag they use. The yachts may have never been navigated to this port for many times. Especially, they are plentiful in the Mediterranean and Caribbean during the winter or summer. The mega yachts will be located in a chosen port while the crew maintains them and waits for Possessors or Guests to arrive. Then, they will make some short sails with the owners aboard. Mega Yachts navigating backward and forward between the Caribbean and Mediterranean in the winter or summer are similar to doing the Milk Run

Common Destinations in France and Italia are Cannes, Antibes, St Tropez, Monte-Carlo Porto Fino, Porto Cervo although the increasing number of Mega yachts are sailing in more distant areas of the world. Among the main ports in the Windward Islands of the Caribbean is Antigua, which hosts Charter Shows when the winter begins. Due to the rising demand for Mega yachts, a lot of custom boat building producers and yacht charter brokers have risen up lately. Luxury yacht building and yacht charter companies are mostly in the United States and Western Europe, but they are also located in Australia, Asia and Eastern Europe. Manufacturers in Europe who are Azimut, Ferretti, AzimutBenetti,Feadship, Sunseeker and Lürssen are at the top of the yacht building market.

Giga yachts are 328 feet in length and still rare, but they are becoming more favored today. The yachts usually have 5 floors above the water surface and 2 below. Manufacturers have facilitated some features being helicopter air-docks, indoor swimming pools and small submarines. Because of the rising number of small luxury yachts, the hyperbolic terms being Giga Yacht has been founded to differentiate the elite group among luxury yachts.