The Sea Folk, or more properly Atha'an Miere (meaning "People of the Sea"), are a seafaring people who live on ships and the islands in the Aryth Ocean and Sea of Storms; indeed, they take every effort to be born, give birth, marry, and die on board one of their ships. They only show up on the mainland to trade goods, until prophecy seemed to be fulfilled (see Coramoor, below). They typically have a dark complexion, and are seen as "exotic" by mainlanders. The rank of a Sea Folk can be determined by both the number of piercings (typically ear and nose, with a chain in between for higher ranks) and the quality of the metal used for the earrings/nose rings.
Sea Folk porcelain sculptures, delicate and graceful objects of art, are highly prized by mainlanders, frequently costing their weight in gold to obtain.
Windfinders
Windfinders can be found on every ship the Sea Folk inhabit. Most Windfinders can channel, and are ranked only under the Sailmistress and Cargomaster on a ship. Windfinders who can channel can typically handle Air and Water most skillfully, creating thick and powerful flows to aid their ship's travel. Conversely, many have little to no skill with Fire or Earth, even less than most female channelers, due to the nature of their society.
Windfinders typically fear being found by Aes Sedai, as they believe the Aes Sedai may take them to the White Tower against their will to train them. Because of this, a Windfinder has the right to refuse passage to a passenger who can channel, something usually reserved for the Sailmistress of the ship.
However, when Nynaeve and Elayne approach the Sea Folk on the orders of the rebel Amyrlin Egwene al'Vere, they comply with many of the Aes Sedai's requests, such as assistance in finding and using the Bowl of The Winds and helping Elayne Trakand maintain Caemlyn's food supplies during the siege, by opening gateways for merchant wagons to travel through.
To allay suspicion among Aes Sedai, the Sea Folk usually send their weakest channelers to the White Tower to give the impression that the One Power does not flow strongly among the Sea Folk and to stop a possible investigation by the Aes Sedai into potential channelling abilities among the Sea Folk.
Culture
The Atha'an Miere are headed by a Mistress of the Ships, roughly equivalent to a queen, but without a fixed geographic territory. Her consort and/or male counterpart is the Master of the Blades, responsible for trade and security concerns. Under this leadership, the Sea Folk are further organized into clans, headed by a Wavemistress. It is unknown at this time whether there is a clan-level counterpart to the Cargomaster. The current Mistress of the Ships is Renaile din Calon Blue Star.
A much lesser-known part of Sea Folk culture is that their vaunted porcelain is actually created by the Amayar, land-dwellers on the island of Tremalking, overseen by a Sea Folk governor. The Amayar apparently follow a pacifistic lifestyle (the "Water Way") very similar to the Tuatha'an Way of the Leaf.
Another little known facet of Sea Folk culture is that both genders go topless while at sea, and out of sight of the mainland. Presumably all of their passengers know this eventually, and keep silent either out of respect/moral outrage, or for more prurient interests. This fact alone may account for why passage on a Sea Folk ship is frequently so costly, although they are also the fastest sailing vessels in the land, and some of the most reliable (partially due to the unrevealed abilities of Windfinders).
The Coramoor
The Sea Folk believe that the Coramoor is predicted by the Jendai Prophecy to lead them to greater glory, including domination of all the seas of the land. Rand al'Thor, who is also the Dragon Reborn and the Car'a'Carn of the Aiel, is believed to be the fulfillment of that prophecy. The Sea Folk will serve the Coramoor in any way they can, but so far they have not pledged formal allegiance to Rand, who has been too busy with mainland matters to meet with them. The recent execution of the Mistress of the Ships by the Seanchan has complicated matters further, until a successor is named.