Gulliver's Travels is a spoof on what is known as the "Traveler's Tales" genre in literature. The narrator "pretends" to be telling a tale about his travels, but the work is a satire on human nature and politics under the guise of a travel tale. During the time that Swift was writing, travel tales were very popular and read by many, hence he decided to write Gulliver's Travels as a mock travel tale.
Lemuel Gulliver, as the narrator, travels around the world. His travels include four voyages: Lilliput; Brobdingnag; Laputa, Balnibarbi, Luggnag, Glubbdubdrib, and Japan; and to the Country of the Houyhnhms. Swift's contemporaries would have found these strange places more believable than we do because at the time (the 1700s), travel to Japan, for example, was almost unheard of, so it was considered an exotic place that no one knew too much about. Swift's descriptions, therefore, were probably not too far-fetched to his readers. No matter how strange the voyage or how weird the people (like the Lilliputians), however, Swift always found plenty to satirze about his contemporary world and country using the travel tale as his vehicle.
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