Unit may refer to:

Arts and entertainment

* UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' *

Unit of action In acting, units of action, otherwise known as bits or beats, are sections that a play's action can be divided into for the purposes of dramatic exploration in rehearsal. The concept was propounded by the Russian actor, director and educator ...

, a discrete piece of action (or beat) in a theatrical presentation

Music

* ''Unit'' (album), 1997 album by the Australian band Regurgitator * The Units, a synthpunk band

Television

* '' The Unit'', an American television series * '' The Unit: Idol Rebooting Project'', South Korean reality TV survival show

Business

Stock keeping unit In inventory management, a stock keeping unit (abbreviated as SKU and pronounced or ) is the unit of measure in which the stocks of a material are managed. Or to put it another way; is a distinct type of item for sale, purchased, or tracked in ...

, a discrete inventory management construct * Strategic business unit, a profit center which focuses on product offering and market segment * Unit of account, a monetary unit of measurement *

Unit coin A challenge coin is a small coin or medallion, bearing an organization's insignia or emblem and carried by the organization's members. Traditionally, they might be given to prove membership when asked and to enhance morale. They are also colle ...

, a small coin or medallion (usually military), bearing an organization's insignia or emblem *

Work unit A work unit or ''danwei'' () is the name given to a place of employment in the People's Republic of China. The term ''danwei'' remains in use today, as people still use it to refer to their workplace. However, it is more appropriate to use ''danwei ...

, the name given to a place of employment in the People's Republic of China

Science and technology

Science and medicine

* Unit, a vessel or section of a

chemical plant A chemical plant is an industrial process plant that manufactures (or otherwise processes) chemicals, usually on a large scale. The general objective of a chemical plant is to create new material wealth via the chemical or biological transform ...

Blood unit Blood transfusion is the process of transferring blood products into a person's circulation intravenously. Transfusions are used for various medical conditions to replace lost components of the blood. Early transfusions used whole blood, but mo ...

, a measurement in blood transfusion * Enzyme unit, a measurement of active enzyme in a sample *

Equivalent (chemistry) An equivalent (symbol: officially equiv; unofficially but often Eq) is the amount of a substance that reacts with (or is ''equivalent'' to) an arbitrary amount (typically one mole) of another substance in a given chemical reaction. It is an arch ...

, a unit of measurement used in chemistry and biology * Geological unit or rock unit, a volume of identifiable rock or ice *

International unit In pharmacology, the international unit (IU) is a unit of measurement for the effect, not mass of a substance; the variance is based on the biological activity or effect, for the purpose of easier comparison across similar ''forms'' of substance ...

, a unit of measurement for nutrients and drugs * Unit of measurement, a definite magnitude of a physical quantity, defined and adopted by convention or by law **

International System of Units The International System of Units, known by the international abbreviation SI in all languages and sometimes pleonastically as the SI system, is the modern form of the metric system and the world's most widely used system of measurement. E ...

(SI), modern form of the metric system ** English units, historical units of measurement used in England up to 1824 ** Humorous units of measurement Some less serious or controversial units ** Unit of length ***

Astronomical unit The astronomical unit (symbol: au, or or AU) is a unit of length, roughly the distance from Earth to the Sun and approximately equal to or 8.3 light-minutes. The actual distance from Earth to the Sun varies by about 3% as Earth orbits t ...

, a unit of length roughly between the Earth and the Sun ** Natural unit, a physical unit of measurement * Unit type, a type allowing only one value in type theory * Unit of alcohol, a measure of the volume of pure ethanol in an alcoholic beverage

Computing

Central processing unit A central processing unit (CPU), also called a central processor, main processor or just processor, is the electronic circuitry that executes instructions comprising a computer program. The CPU performs basic arithmetic, logic, controlling, an ...

, the electronic circuitry within a computer that carries out the instructions of a computer program * GNU Units, a software program for unit conversion *

Rack unit A rack unit (abbreviated U or RU) is a unit of measure defined as . It is most frequently used as a measurement of the overall height of 19-inch and 23-inch rack frames, as well as the height of equipment that mounts in these frames, whereby th ...

, a unit of measure most commonly used to define the size of certain computing equipment

Mathematics

Unit (ring theory) In algebra, a unit of a ring is an invertible element for the multiplication of the ring. That is, an element of a ring is a unit if there exists in such that vu = uv = 1, where is the multiplicative identity; the element is unique for this ...

, an element that is invertible with respect to ring multiplication * Unit, identity element * Unit, a

tuple In mathematics, a tuple is a finite ordered list (sequence) of elements. An -tuple is a sequence (or ordered list) of elements, where is a non-negative integer. There is only one 0-tuple, referred to as ''the empty tuple''. An -tuple is defi ...

of length 0; an empty tuple * Statistical unit, a data point on which statistical analysis is performed *

Unit angle The radian, denoted by the symbol rad, is the unit of angle in the International System of Units (SI) and is the standard unit of angular measure used in many areas of mathematics. The unit was formerly an SI supplementary unit (before that c ...

, a full turn equal to an angle of 1 *

Unit circle In mathematics, a unit circle is a circle of unit radius—that is, a radius of 1. Frequently, especially in trigonometry, the unit circle is the circle of radius 1 centered at the origin (0, 0) in the Cartesian coordinate system in the Eucl ...

, a circle with a radius of length 1 * Unit cube, a cube with sides of length 1 * Unit fraction, a reciprocal of a positive integer *

Unit imaginary number The imaginary unit or unit imaginary number () is a solution to the quadratic equation x^2+1=0. Although there is no real number with this property, can be used to extend the real numbers to what are called complex numbers, using addition and ...

, square root of negative 1

(\sqrt)

Unit impulse Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (alb ...

, an impulse of height 1 *

Unit interval In mathematics, the unit interval is the closed interval , that is, the set of all real numbers that are greater than or equal to 0 and less than or equal to 1. It is often denoted ' (capital letter ). In addition to its role in real analysis, ...

, an interval of distance 1 *

Unit matrix In linear algebra, the identity matrix of size n is the n\times n square matrix with ones on the main diagonal and zeros elsewhere. Terminology and notation The identity matrix is often denoted by I_n, or simply by I if the size is immaterial or ...

, a diagonal matrix such that all elements on the main diagonal are 1 and all the others are zero * Unit number, the number 1 *

Unit round-off Machine epsilon or machine precision is an upper bound on the relative approximation error due to rounding in floating point arithmetic. This value characterizes computer arithmetic in the field of numerical analysis, and by extension in the subjec ...

, an upper bound on the relative error due to rounding in floating point *

Unit set Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (al ...

, a singleton, a set with exactly 1 element * Unit sphere, a sphere with a radius of length 1 *

Unit square In mathematics, a unit square is a square whose sides have length . Often, ''the'' unit square refers specifically to the square in the Cartesian plane with corners at the four points ), , , and . Cartesian coordinates In a Cartesian coordinate ...

, a square with sides of length 1 *

Unit vector In mathematics, a unit vector in a normed vector space is a vector (often a spatial vector) of length 1. A unit vector is often denoted by a lowercase letter with a circumflex, or "hat", as in \hat (pronounced "v-hat"). The term ''direction vecto ...

, a vector with length equal to 1

Military

* Active service unit, the former Provisional Irish Republican Army cell *

Military unit Military organization or military organisation is the structuring of the armed forces of a state so as to offer such military capability as a national defense policy may require. In some countries paramilitary forces are included in a nation' ...

, an homogeneous military organization whose administrative and command functions are self-contained * Sayeret Matkal (The Unit), the Israeli special forces unit

Other uses

Unit (Cristian Fleming) Unit is an electronic musician based in New York City. Unit began releasing electronic music officially at the age of 25, although he had musical involvement for many years prior, playing bass guitar at 17, and began working on electronic music at ...

(born 1974), electronic musician based in New York City *

Unit (housing) A housing unit, or dwelling unit, (at later mention often abbreviated to ''unit'') is a structure or the part of a structure or the space that is used as a home, residence, or sleeping place by one person or more people who maintain a common hous ...

, a self-contained suite of rooms within a set of similar dwellings * Unit (Norway), a government directorate * Unit, course credit at a school or other educational institution *

Multiple unit A multiple-unit train or simply multiple unit (MU) is a self-propelled train composed of one or more carriages joined together, which when coupled to another multiple unit can be controlled by a single driver, with multiple-unit train contr ...

, self-propelled train carriage capable of coupling other units of the same type