Laputa is a fictional flying island or rock with an adamantine base, that can be maneuvered by its inhabitants in any direction using magnetic levitation. The population of the island mainly consists of educated people, who are fond of mathematics, astronomy, music and technology, but fail to make practical use of their knowledge (the rest are their servants).
They had mastered magnetic levitation and discovered the two moons of Mars (which in reality would not be discovered for another 150 years), but couldn't construct well-designed clothing or buildings - reason for this being that measurements are taken with instruments such as quadrants and a compass rather than with tapes.
It is a male-dominated society; often, the wives of these men request to leave the island to visit the land below. However, these requests are almost never granted because the women never want to come back voluntarily.
The ground below the floating island, within the region it can travel, is also controlled by the king of Laputa, with the ground capital being the city of Lagado.
The king, being a tyrannic ruler, controls the mainland mostly by threatening to cover rebel regions with the island's shadow, thus preventing sunlight and rain, or by throwing rocks at rebellious surface cities (which seems the first time that aerial bombardment was conceived of as a method of warfare). In extreme cases, the island is lowered on the cities below in order to crush them, although this has not been successful every time, notably in the case of Lindalino.
The rebelling of Lindalino against Laputa is an allegory on Ireland's revolt against England, and England's (meaning: the Whig government's) violent foreign and internal politics (see Jonathan Swift for his political career).
As "la puta" means "the whore," (see Spanish profanity) some Spanish editions of "Gulliver's Travels" use "Lapuntu" and "Lupata" as euphemisms. It's very likely, given Swift's way of satire, that he was well aware of the Spanish meaning (Gulliver himself claimed Spanish among the many languages in which he was fluent).
Some find a parallel with Martin Luther's famous quote "That great whore, Reason", given Laputians' extreme fondness of reason. However, that Swift's intention was to mock the so-called "Age of Reason" is not without doubt, given the story-teller's great admiration of Houyhnhnms for their rational thinking.
Laputa, as some of Swift's other inventions, was the inspiration and basis for several other works; this may be due to the universally appealing nature of the concept of a land floating in sky, or the popular stereotyping of intellectuals as an otherworldly culture.
Works based on Laputa include:
"JC Denton: I know your UNATCO killphrase: Laputan machine." "Gunther Hermann: I am not a mach..." "JC Denton: Sticks and stones. "