Great Sea

The Great Sea is the setting in which the events of The Wind Waker take place. In Phantom Hourglass, the Great Sea only makes an appearance during the introduction and ending sequences of the game.

In-game, the Great Sea is restricted to an area of 7x7 1000-unit squares, each containing an island of its own.

History
Many years before The Wind Waker begins, the land of Hyrule is flooded by the Gods as a last resort to stop Ganon's forces when The Hero of Time didn't arrive to destroy them. Its surviving people flee to the mountain-tops and try to restore peaceful life. Those mountain-tops became the many islands of The Great Sea. Many years pass, and the people forget about the "Old" Hyrule, except in a bedtime story told to children, and in a coming of age ceremony for young boys.

Islands
Main Article: Great Sea Islands Most of the islands in the Great Sea are quite small, with little intelligent life inhabiting them. The chief island is Windfall, which has the only major village, exept for a small settlement on Outset. There was a large pirate hideout at the Forsaken Fortress, until recently. Some of the more prominent islands include:
 * Dragon Roost Island
 * Forest Haven
 * Forsaken Fortress
 * Tower of the Gods
 * Headstone Island
 * Gale Isle

People
There are many people in the great sea, but the main group is Hyrulean. They live on Windfall and Outset Island, but they are also scattered around. The Rito live on Dragon Roost Island, and the Koroks reside on Forest Haven with the Great Deku Tree. Gorons in this game are in the form of Goron Merchants. The wherabouts of the Zora are unknown, also a fish creature called Jabun is in this game, obviously someone like Jabu-Jabu. There are at least one group of pirates, Tetra's gang, but there probably was or is some more that are not seen in-game.

Economy
Like in most lands in the Zelda universe, and because of the fact that the Great Sea is born from Hyrule, rupees are the mean of currency, which is accepted in every inhabited island in the game. However, the economy is a bit more diverse than in the former land of Hyrule, given the different businesses run; for example, Goron Merchants fuel trading sequences by selling their goods to travelers and also sending them to major shops and retails to give townspeople access to them. Auctions are run in Windfall Island every night, and shop ships can be seen sailing around numerous islands as well.

Technology in the Great Sea
The weaponry in the Great Sea is more advanced than it was in Hyrule before its flood. Navigating across the waters are cannon boats capable of shooting at enemies from far distances. It's unknown whether these boats are piloted manually or work automatically (in the latter case, it would indeed prove how much advancement is shown in matter of technology in the Great Sea). Mounted in coral reefs and high platforms are wall-placed belic cannons that can shoot bombs to distant enemies, and they do operate on their own.

Advanced tools and devices can be found as well, such as the Tingle Tuner (which allows communication between the user and an assistant for various purposes), color-recording Picto Boxes (used to take pictographs that become important for figurine making, and pieces of ancient technology (as seen in Tower of the Gods and Wind Temple). Aside from this, it's unknown how much Hyrule had progressed in this aspect before being flooded, thus it's unknown how much was lost before the aforementioned divine intervention.

Trivia

 * Contrary to popular belief, the Great Sea is not the setting in which most of the events of Phantom Hourglass take place. Link, Tetra and the rest of the pirate crew are only navigating the Great Sea during the introduction and ending sequences of the game; the rest of the time is spent in a new sea with the implied name of the World of the Ocean King.
 * The Great Sea is also a stage in Super Smash Bros. Brawl, although the stage is called Pirate Ship.