# EM

EM, Em or em may refer to:

## Arts and entertainment
### Music

* EM, the E major musical scale
* Em, the E minor musical scale
* Electronic music, music that employs electronic musical instruments and electronic music technology in its production
* Encyclopedia Metallum, an online metal music database
* Eminem, American rapper

### Other uses in arts and entertainment

* Em (comic strip), a comic strip by Maria Smedstad

## Companies and organizations

* Em (restaurant), a restaurant in Mexico City
* Aero Benin (IATA code), a defunct airline
* Empire Airlines (IATA code), a charter and cargo airline based in Idaho, US
* Erasmus Mundus, an international student-exchange program
* Estado de Minas, a Brazilian newspaper
* European Movement, an international lobbying association
* ExxonMobil, a large oil company formed from the merger of Exxon and Mobil in 1999
* La République En Marche! (sometimes shortened to "En Marche!"), a major French political party

## Economics

* Emerging markets, nations undergoing rapid industrialization

## Language and typography
### Language

* M, a letter of the modern Latin alphabet, in English and other languages
* Em (Cyrillic) (М / м), a letter of the Cyrillic alphabet
* Em (digraph), a digraph in Portuguese
* Em, the third-person singular oblique Spivak pronoun

### Typography

* em (typography), a unit of measurement
* em dash, a dash that is one em wide
* em space or mutton, a space that is one em wide

## Management

* Emergency management, a discipline that studies dealing with and avoiding risks
* Energy management, planning and operation of energy production and energy consumption units
* Environmental management, the management of the interaction of human societies with the environment

## Places

* El Monte, California, a city in the United States
* El Monte, Chile, a city in Chile

## Science
### Biology

* Effective microorganisms, a series of products intended to improve soil quality and plant growth
* Extracellular matrix, the connective tissue supporting cells in multicellular organisms
* Membrane potential (E$_m$), of a cell

### Computing

* <em>...</em>, emphasis HTML element
* End of medium, ISO C0 control code ^Y
* Empirical modelling
* em (typography), a unit of measurement in Web design
* eM Client E-Mail client

### Medicine

* Emergency medicine, a medical specialty dealing with acute illnesses and injuries that require immediate attention
* Erythema multiforme, a skin condition that usually follows an antecedent infection or drug exposure
* Erythromelalgia, a disorder that typically affects the skin of the feet and/or hands, causing redness, heat and pain
* Extensive metabolizer, a term used in pharmacogenomics to refer to individuals with normal metabolic activity

### Physics

* Exametre or exameter (Em), an SI unit of length equal to 10$^{18}$ metres
* Electromagnetic spectrum, the range of all possible frequencies of electromagnetic radiation
* Electromigration, the transport of conducting solid material caused by electric current through it
* Electromagnetism, one of the fundamental physical forces
* Electromechanics, combines electrical engineering and mechanical engineering

### Other uses in science and technology

* Nikon EM, an SLR camera made by the Nikon Corporation in the late 1970s
* Electron microscope, a type of microscope that uses electrons to "illuminate" a specimen and create an enlarged image
* Electron multiplier, a vacuum-tube structure that multiplies incident charges by means of secondary emission
* Electronic monitoring, a form of surveillance used in criminal justice
* Atlantic Equatorial mode, a climate pattern of the Atlantic Ocean
* Expectation–maximization algorithm, an algorithm for finding maximum likelihood estimates of parameters in probabilistic models

## Other uses

* Electrician's mate, an occupational rating in the U.S. Navy and U.S. Coast Guard
* David Em (born 1952), an American computer art pioneer
* EM gauge, a scale used in model railways
* Etymologicum Magnum, in the bibliography of the largest Byzantine lexicon