Io, IO, iO, I/O, i/o, or i.o. may refer to: * Io (mythology), daughter of Inachus in Greek mythology, and lover of Zeus who was turned into a cow *

Io (moon) Io (), or Jupiter I, is the innermost and third-largest of the four Galilean moons of the planet Jupiter. Slightly larger than Earth’s moon, Io is the fourth-largest moon in the Solar System, has the highest density of any moon, the strong ...

, a moon of Jupiter

Arts and media

Fictional elements

Scylla Io The following list comprises the various antagonistic factions that appear in the manga ''Saint Seiya'' and the sequel '' Saint Seiya: Next Dimension'', written and illustrated by Masami Kurumada. The antagonistic characters appear as various de ...

, one of Poseidon's Marine Generals in the ''Saint Seiya'' series *A ''Dungeons & Dragons'' dragon deity *Io Otonashi, a main character in the Japanese manga series ''

Place to Place is a Japanese four-panel manga series written and illustrated by Ishiki. The manga began serialisation in Houbunsha's ''Manga Time Kirara'' magazine in 2006 and the chapters collected into 9 volumes as of 27 September 2022. An anime televi ...

'' (''Acchi Kocchi'')

Gaming

*''iO'', a 2014 video game by

Gamious Gamious is a Dutch video game developer and publisher founded in Haarlem, Netherlands ) , anthem = ( en, "William of Nassau") , image_map = , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of the Ne ...

* IO Interactive, a Danish computer game developer

Music

IO (German band) IO (pronounced the English way 'eye-oh', as opposed to the German way 'ee-oh') is a German alternative rock band, formed in 2006 after the breakup of Guano Apes. Original Guano Apes members Henning Rümenapp (guitar), Stefan Ude ( bass) and Dennis ...

, a German band *

Io (English band) io is an English experimental rock band from Birmingham, England. The band currently consists of Al Lawson (guitar/vocals), Stu Atkins (guitar), Dave Wright (drums), and Steve Wood (bass). The band formed in 2006 after the collapse of two B ...

, an English band *

I_o (musician) Garrett Falls Lockhart (May 16, 1990 – November 23, 2020), known professionally by his stage name i_o, was an American electronic dance music DJ and record producer. Early life Garret Falls Lockhart was born on May 16, 1990, in Richmond, ...

, an American DJ and record producer (1990–2020)

Theatre and opera

* ''Io'' (opera), an unfinished ''acte de ballet'' (opera) by Jean-Philippe Rameau *

iO Theater iO, or iO Chicago, (formerly known as "ImprovOlympic") is an improv theater and training center in central Chicago, with a former branch in Los Angeles, called iO West and in Raleigh, North Carolina called iO South. The theater taught and hosted p ...

(ImprovOlympic), a theater in Chicago, Illinois, dedicated to improvisational comedy *

IO West The iO West (formerly known as the "ImprovOlympic West") was the Los Angeles branch of the iO in Chicago. The theater was located at 6366 Hollywood Blvd., in Hollywood, California. In addition to presenting improv and sketch comedy shows ever ...

, a Los Angeles theater associated with the Chicago iO

Other uses in arts and media

* ''Io'' (film), a 2019 Netflix film *

iO Digital Cable Service Optimum is an American Internet, television, mobile and home phone company serving Arizona, Arkansas, California, Connecticut, Idaho, Kentucky, Louisiana, Mississippi, Missouri, New Jersey, New York, North Carolina, Oklahoma, Pennsylvania, Texas ...

, a service offered by Cablevision *'' International Organization'', a peer-reviewed journal that covers the entire field of international affairs

Business and economics

Industrial and organizational psychology Industrial and organizational psychology (I-O psychology), an applied discipline within psychology, is the science of human behavior in the workplace. Depending on the country or region of the world, I-O psychology is also known as occupational ...

, the field of psychology that studies work, academic, and other organizational issues * Industrial organization, the field of economics that studies the strategic behavior of firms, the structure of markets and their interactions *

Insertion order Insertion may refer to: *Insertion (anatomy), the point of a tendon or ligament onto the skeleton or other part of the body *Insertion (genetics), the addition of DNA into a genetic sequence *Insertion, several meanings in medicine, see ICD-10-PCS ...

, a business document specifying the inventory goal of an advertising campaign * Integrated operations, a term used in the petroleum industry describing new work processes and ways of working that have been facilitated by modern information and communication technologies *Interest-only, a type of

collateralized mortgage obligation A collateralized mortgage obligation (CMO) is a type of complex debt security that repackages and directs the payments of principal and interest from a collateral pool to different types and maturities of securities, thereby meeting investor need ...

(CMO) or mortgage-backed security

Language

* i.o., ', Latin phrase meaning "respectively" ("in that order") *

Io (princely title) ''Io'' (Church Slavonic: Ιω, Їѡ and Иѡ, also Iωан and Iωнь; Romanian Cyrillic: Iѡ; el, Ίω) is the contraction of a title used mainly by the royalty (hospodars or voivodes) in Moldavia and Wallachia, preceding their names and the ...

, a particle of a title used by Moldavian and Wallachian Princes-regnant *

Ido language Ido () is a constructed language derived from Reformed Esperanto, and similarly designed with the goal of being a universal second language for people of diverse backgrounds. To function as an effective ''international auxiliary language'', I ...

(ISO 639-1 language code IO), a constructed language * Indirect object, the object that is the recipient of an action (by a verb)

Mythology

* Io (mythology), daughter of Inachus in Greek mythology, and lover of Zeus who was turned into a cow *Io, an alternate spelling of the nereid

Ino Ino or INO may refer to: Arts and music *I-No, a character in the ''Guilty Gear'' series of video games *Ino (Greek mythology), a queen of Thebes in Greek mythology *INO Records, an American Christian music label *Ino Yamanaka, a character in th ...

, later known as Leukothea, who in the Odyssey gave Odysseus a veil that allowed him to breathe underwater *

Io Matua Kore Io Matua Kore is often understood as the supreme being in Polynesian narrative, particularly of the Māori people. Io does seem to be present in the mythologies of other Polynesian islands including Hawai‘i, the Society Islands, and the Cook ...

, in some Māori traditions the supreme god

People

*, Japanese shogi player *, Japanese manga artist * Io Shirai (born 1990), Japanese professional wrestler *, Japanese manga artist *

iO Tillett Wright iO Tillett Wright (born September 2, 1985) is an American author, photographer, actor, TV and podcast host, and activist. After growing up in New York City, he founded street art magazine ''Overspray'' and served as its editor-in-chief until 20 ...

(born 1985), American artist, director, photographer, writer, film maker, activist, and actor

Places on Earth

Io (island) Io ( el, Ίο), is an uninhabited Greek islet, close to the coast of Lasithi, eastern Crete, and in the Libyan Sea. It is part of the Lefki municipality. See also *List of islands of Greece Greece has many islands, with estimates ranging ...

, an uninhabited islet near Crete, Greece *

Io, Norway Io is a village in Alver municipality, in Vestland county, Norway. The village sits on the shore of the Herdlefjorden along the northern coast of the island of Holsnøy, about southwest of the village of Rossland. See also *List of short plac ...

, a village in Alver, Norway *

Mount Iō (disambiguation) Mount Iō also Mount Iwo may refer to: * Mount Iō (Akan), in Akan National Park in Hokkaidō. * Mount Iō (Iōjima), in Kagoshima prefecture on the island of Iōjima. * Mount Iō (Shiretoko), in Shiretoko National Park in Hokkaidō. * Mount Iō (Y ...

, name of several mountains in Japan *

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by th ...

Science and technology

Astronomy

, a moon of Jupiter *

85 Io Io (minor planet designation: 85 Io is carbonaceous asteroid from the central region of the asteroid belt, approximately 170 kilometers in diameter. It is an identified Eunomian interloper. Discovery and naming It was discovered by C. H. F ...

, an asteroid

Biology and medicine

* ''Io'' (gastropod), a genus of freshwater snail in the family Pleuroceridae *''

Automeris io ''Automeris io'', the Io moth () or peacock moth, is a colorful North American moth in the family Saturniidae. The io moth is also a member of the subfamily Hemileucinae. The name Io comes from Greek mythology in which Io was a mortal lover of ...

'', a moth species in North America *''

Aglais io ''Aglais io'', the European peacock, more commonly known simply as the peacock butterfly, is a colourful butterfly, found in Europe and temperate Asia as far east as Japan. It was formerly classified as the only member of the genus ''Inachis'' ( ...

'', the European peacock butterfly *

Intraosseous infusion Intraosseous infusion (IO) is the process of injecting medications, fluids, or blood products directly into the marrow of a bone; this provides a non-collapsible entry point into the systemic venous system. The intraosseous infusion technique is ...

, the medical process of introducing medication directly into the bone marrow * Hawaiian hawk, in the local dialect *

Immuno-oncology Cancer immunotherapy (sometimes called immuno-oncology) is the stimulation of the immune system to treat cancer, improving on the immune system's natural ability to fight the disease. It is an application of the fundamental research of cancer ...

, another term for cancer immunotherapy

Computing

* .io, the Internet country code top-level domain (ccTLD) for the British Indian Ocean Territory * Io (programming language), a pure object-oriented programming language *

IO.SYS is an essential part of MS-DOS and Windows 9x. It contains the default MS-DOS device drivers (hardware interfacing routines) and the DOS initialization program. Boot sequence In the PC bootup sequence, the first sector of the boot disk is ...

, a system file in Microsoft DOS and Windows 95, 98 and ME *

Indistinguishability obfuscation In cryptography, indistinguishability obfuscation (abbreviated IO or iO) is a type of software obfuscation with the defining property that obfuscating any two programs that compute the same mathematical function results in programs that cannot b ...

, a cryptographic tool to obscure computer code *

Input/output In computing, input/output (I/O, or informally io or IO) is the communication between an information processing system, such as a computer, and the outside world, possibly a human or another information processing system. Inputs are the signals ...

, the collection of interfaces that different functional units of an information processing system use to communicate with each other

Other uses in science and technology

Ionium Thorium (90Th) has seven naturally occurring isotopes but none are stable. One isotope, 232Th, is ''relatively'' stable, with a half-life of 1.405×1010 years, considerably longer than the age of the Earth, and even slightly longer than the gene ...

(symbol Io), a claimed chemical element that was later realized to be thorium-230 *

Image orthicon tube Video camera tubes were devices based on the cathode ray tube that were used in television cameras to capture television images, prior to the introduction of charge-coupled device (CCD) image sensors in the 1980s. Several different types of tub ...

, a TV camera used between 1946 and 1968 *Infinitely often, a mathematics term sometimes written "i.o."; see an example in

set-theoretic limit In mathematics, the limit of a sequence of sets A_1, A_2, \ldots (subsets of a common set X) is a set whose elements are determined by the sequence in either of two equivalent ways: (1) by upper and lower bounds on the sequence that converge monot ...

Other uses

Bureau of International Organization Affairs The Bureau of International Organization Affairs (IO) is a bureau in the United States Department of State that creates and executes U.S. policy in the United Nations and other international organizations. It is headed by the Assistant Secreta ...

, in the U.S. Department of State * Government Printing Bureau (Macau), known in Portuguese as the ''Imprensa Oficial'' or "IO" *

Indonesian Airlines Indonesian Airlines (PT Indonesian Airlines Aviapatria) was an airline based in Jakarta, Indonesia. It operated domestic services. The Transportation Ministry in February 2007 delayed license revocation of 11 idle airlines, including Indonesia ...

(IATA airline designator IO) *Investigating Officer, a member of

law enforcement in the United Kingdom Law enforcement in the United Kingdom is organised separately in each of the legal systems of the United Kingdom: England and Wales, Northern Ireland and Scotland. Most law enforcement is carried out by police officers serving in regional pol ...

who heads an investigation *

Mitsubishi Pajero iO The Mitsubishi Pajero iO is a mini SUV produced by the Japanese manufacturer Mitsubishi between 1999 (since June 15, 1998, in three-door form, and August 24, 1998, as a five-door) and 2007. The "iO" name is derived from the Italian for "I" which, ...

, a mini SUV model produced by Mitsubishi Motors