In Greek mythology, the beautiful daughter of Inachus, king of Argos, Greece, who was changed by Hera (Juno), in a fit of jealousy, into a white heifer, and placed under the watch of Argus of the hundred eyes. When Argus was killed by Hermes at the command of Zeus, the heifer was maddened by a terrible gadfly sent by Hera, and wandered about until she arrived in Egypt. There she recovered her original shape, and bore Epaphus to Zeus. Epaphus became the ancestor of Ægyptus, Damaus, Cepheus, and Phineus. She was identified by the Egyptians with Isis. According to another legend, Io was carried off by Phoenician traders who landed in Argos. The myth is generally explained to be Aah or the moon wandering in the starry skies, symbolized by the hundred-eyed Argus; her transformation into a horned heifer representing the crescent moon.

One of the large moons of the planet Jupiter, remarkable for its intense volcanic activity, as observed in fly-bys of space probes. It was named after the mythological Io.

(Greek mythology) a maiden seduced by Zeus; when Hera was about to discover them together Zeus turned her into a white heifer

Io is an unfinished opera by Jean-Philippe Rameau in the form of a one-act acte de ballet. The date of its composition is unknown and it was probably unperformed during Rameau's lifetime. The name of its librettist is also unknown, but was probably Louis de Cahusac.

Io is a particle of a title used exclusively by Romanian royalty from both Moldavia and Walachia, preceding their names and the complete list of titles, in all their documents (written or engraved), since the formation of the respective principalities up to the Hohenzollern dynasty in the 19th century.

An exclamation of joy or triumph; -- often interjectional.

Io is a pure object-oriented programming language inspired by Smalltalk, Self, Lua, Lisp and Newton Script. Io has a prototype-based object model similar to the ones in Self and NewtonScript, eliminating the distinction between instance and class. Like Smalltalk, everything is an object and there is dynamic typing.

Io is a program to classify high-throughput genomics data in the Gene Ontology. Io includes a statistical estimation of the significance of data in the GO nodes and reannotation files for Affymetrix chips.

In many campaign settings for the Dungeons & Dragons roleplaying game, Io is the chief deity worshipped by dragons.

This article deals with the Space Station Io, as presented in the science fiction universe of the television show Babylon 5.

Independence Office

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