QR may refer to:

Arts and entertainment

* Nippon Cultural Broadcasting (from call sign JOQR), a Tokyo radio station * Queen's Radio, a student radio station at Queen's University Belfast * Quiet Riot, an American rock band

Businesses

Qatar Airways Qatar Airways Company Q.C.S.C. ( ar, القطرية, ''al-Qaṭariya''), operating as Qatar Airways, is the state-owned flag carrier airline of Qatar. Headquartered in the Qatar Airways Tower in Doha, the airline operates a hub-and-spoke networ ...

(IATA code) *

Queensland Rail Queensland Rail (QR) is a railway operator in Queensland, Australia. Owned by the Queensland Government, it operates local and long-distance passenger services, as well as owning and maintaining approximately 6,600 kilometres of track and relate ...

, a company responsible for the railway system in Queensland, Australia *

Quintana Roo (company) Quintana Roo (QR) was the first company to create a triathlon-specific wetsuit over 25 years ago, and then a tri-specific bicycle two years later. The company was founded in 1987 by Dan Empfield of Ironman fame and is currently owned by the Ameri ...

, a triathlon-specific wetsuit and bicycle company

Places

Quintana Roo Quintana Roo ( , ), officially the Free and Sovereign State of Quintana Roo ( es, Estado Libre y Soberano de Quintana Roo), is one of the 31 states which, with Mexico City, constitute the 32 federal entities of Mexico. It is divided into 11 mu ...

, a state of Mexico *

Karakalpakstan Karakalpakstan, / officially the Republic of Karakalpakstan, / is an autonomous republic of Uzbekistan. It occupies the whole northwestern part of Uzbekistan. The capital is Nukus (' / ). The Republic of Karakalpakstan has an area of , and ...

(Qoraqalpog'iston Respublikasi), Uzbekistan (ISO 3166-2 subcode UZ-QR)

Science and technology

QR code A QR code (an initialism for quick response code) is a type of Barcode#Matrix (2D) barcodes, matrix barcode (or two-dimensional barcode) invented in 1994 by the Japanese company Denso#Denso Wave, Denso Wave. A barcode is a machine-readable optic ...

(Quick Response code), a two-dimensional code * ATCvet code QR ''Respiratory system'', a section of the Anatomical Therapeutic Chemical Classification System for veterinary medicinal products * DICOM Q/R,

DICOM Digital Imaging and Communications in Medicine (DICOM) is the standard for the communication and management of medical imaging information and related data. DICOM is most commonly used for storing and transmitting medical images enabling the integ ...

Query / Retrieve * Nissan QR engine

Mathematics

QR decomposition In linear algebra, a QR decomposition, also known as a QR factorization or QU factorization, is a decomposition of a matrix ''A'' into a product ''A'' = ''QR'' of an orthogonal matrix ''Q'' and an upper triangular matrix ''R''. QR decom ...

, a decomposition of a matrix * QR algorithm, an eigenvalue algorithm using QR decomposition *

Quadratic reciprocity In number theory, the law of quadratic reciprocity is a theorem about modular arithmetic that gives conditions for the solvability of quadratic equations modulo prime numbers. Due to its subtlety, it has many formulations, but the most standard s ...

, a theorem from modular arithmetic * Quasireversibility, a property of some queues * Reaction quotient (Q_r), a function of the activities or concentrations of the chemical species involved in a chemical reaction

Other uses

* ''

Quarterly Review The ''Quarterly Review'' was a literary and political periodical founded in March 1809 by London publishing house John Murray. It ceased publication in 1967. It was referred to as ''The London Quarterly Review'', as reprinted by Leonard Scott, f ...

'', a defunct literary and political periodical * Qatari riyal, the currency of Qatar {{disambiguation