Dual or Duals may refer to:

Paired/two things

Dual (mathematics) In mathematics, a duality translates concepts, theorems or mathematical structures into other concepts, theorems or structures in a Injective function, one-to-one fashion, often (but not always) by means of an Involution (mathematics), involution ...

, a notion of paired concepts that mirror one another **

Dual (category theory) In category theory, a branch of mathematics, duality is a correspondence between the properties of a category ''C'' and the dual properties of the opposite category ''C''op. Given a statement regarding the category ''C'', by interchanging the s ...

, a formalization of mathematical duality *** see more cases in :Duality theories * Dual number, a number system used in automatic differentiation *

Dual (grammatical number) Dual ( abbreviated ) is a grammatical number that some languages use in addition to singular and plural. When a noun or pronoun appears in dual form, it is interpreted as referring to precisely two of the entities (objects or persons) identifie ...

, a grammatical category used in some languages * Dual county, a Gaelic games county which competes in both Gaelic football and hurling * Dual diagnosis, a psychiatric diagnosis of co-occurrence of substance abuse and a mental problem * Dual fertilization, simultaneous application of a P-type and N-type fertilizer * Dual impedance, electrical circuits that are the dual of each other * Dual SIM cellphone supporting use of two SIMs * Aerochute International Dual a two-seat Australian powered parachute design

Acronyms and other uses

* Dual (brand), a manufacturer of Hifi equipment * DUAL (cognitive architecture), an artificial intelligence design model * DUAL algorithm, or diffusing update algorithm, used to update Internet protocol routing tables * Dual language, alternative spelling of the Australian Aboriginal Dhuwal language *

DUAL table The DUAL table is a special one-row, one-column table present by default in Oracle and other database installations. In Oracle, the table has a single VARCHAR2(1) column called DUMMY that has a value of 'X'. It is suitable for use in selecting a ...

, a special one-row and one-column database table * Dual-Ghia, US-brand of luxury-car of the late 1950s

Media

* ''Dual'' (2008 film), a 2008 western drama film * ''Dual'' (2022 film), a 2022 science fiction thriller film * "Dual" (''Heroes''), an episode of ''Heroes'' *

Dual! Parallel Trouble Adventure is a Japanese anime series animated by AIC and created by Masaki Kajishima, best known for the '' Tenchi Muyo!'' franchise. It was originally broadcast on Wowow from April to July 1999 and was licensed in the US by Pioneer LDC, later k ...

, an anime series * ''Dual'' (album), an album of traditional Scottish and Irish music recorded by Éamonn Doorley, Muireann Nic Amhlaoibh, Julie Fowlis and Ross Martin, released 2008 * ''Dual'' (EP), a 2013 EP by Sampha * ''

Duals ''Duals'' is a compilation album by the Irish rock band U2. It was released in April 2011 to u2.com subscribers. Track listing :* "Where the Streets Have No Name" and "Amazing Grace" are studio mix of U2's performance at the Rose Bowl, ...

'', an album by U2 *

The Duals The Duals were an American surf rock duo formed in Los Angeles, California, in 1961. Much of the collaboration's music capitalized on the style of music popularized in Southern California in the early 1960s. They reached the national charts wit ...

, American duo

Paired/two things

Acronyms and other uses

Media

See also