IOI may refer to: * Idiopathic orbital inflammatory disease *

International Olympiad in Informatics The International Olympiad in Informatics (IOI) is an annual competitive programming competition and one of the International Science Olympiads Student competition, for secondary school students. The first IOI was held in 1989 in Pravetz, Bulgar ...

Interonset interval In music a time point or ''timepoint'' ( point in time) is "an instant, analogous to a geometrical point in space". Because it has no duration, it literally cannot be heard, but it may be used to represent "the point of initiation of a single pit ...

* Indication of interest, used in financial trading * Interest on Investment, a synonym for Return on Investment (ROI) *

Island of Ireland Ireland (, ; ; Ulster-Scots: ) is an island in the North Atlantic Ocean, in Northwestern Europe. Geopolitically, the island is divided between the Republic of Ireland (officially named Irelanda sovereign state covering five-sixths of th ...

, used to refer to the entire geographical entity encompassing both the

Republic of Ireland Ireland ( ), also known as the Republic of Ireland (), is a country in Northwestern Europe, north-western Europe consisting of 26 of the 32 Counties of Ireland, counties of the island of Ireland, with a population of about 5.4 million. ...

( ROI) and

Northern Ireland Northern Ireland ( ; ) is a Countries of the United Kingdom, part of the United Kingdom in the north-east of the island of Ireland. It has been #Descriptions, variously described as a country, province or region. Northern Ireland shares Repub ...

( NI). *

IO Interactive IO Interactive A/S (IOI) is a Danish video game developer and publisher based in Copenhagen, best known for creating and developing the ''Hitman'' and '' Kane and Lynch'' franchises. IO Interactive's most recent game is '' Hitman 3'', which was ...

, a Danish video game developer * International Ombudsman Institute *

IOI Group IOI Corporation Berhad, commonly referred to as IOI, was incorporated on 31 October 1969 as Industrial Oxygen Incorporated Sdn Bhd. IOI is one of Malaysia's biggest conglomerates. It ventured into oil palm plantations in 1983, followed by pro ...

, a Malaysian conglomerate * I.O.I, a South Korean girl group formed from the television show ''Produce 101'' * Innovative Online Industries (IOI), the fictional corporation that employs most of the antagonists of the 2011 novel '' Ready Player One'' and its 2018 film adaptation

See also