B is the second letter of the Latin alphabet. B may also refer to:

Science, technology, and mathematics

Astronomy

* Astronomical objects in the Barnard list of dark nebulae (abbreviation B) * Latitude (''b'') in the galactic coordinate system

Biology and medicine

* Haplogroup B (mtDNA), a human mitochondrial DNA (mtDNA) haplogroup * Haplogroup B (Y-DNA), a Y-chromosomal DNA (Y-DNA) haplogroup * Blood type B * ATC code B ''Blood and blood forming organs'', a section of the Anatomical Therapeutic Chemical Classification System * Vitamin B * Hepatitis B *

Berlin Botanical Garden and Botanical Museum The Berlin Botanic Garden and Botanical Museum (german: link=no, Botanischer Garten und Botanisches Museum Berlin) is a botanical garden in the locality of the borough of , Berlin, Germany. Constructed between 1897 and 1910 under the guidance ...

, assigned the abbreviation B as a repository of herbarium specimens

Computing

* B (programming language) * B-Method, for computer software development * B-tree, a data structure * Bit (b) * Byte (B) * , an

HTML element An HTML element is a type of HTML (HyperText Markup Language) document component, one of several types of HTML nodes (there are also text nodes, comment nodes and others). The first used version of HTML was written by Tim Berners-Lee in 1993 ...

denoting bold text

Physical and chemical quantities and units

* One of the reciprocal lattice vectors (''b*'') * Breadth (''b''); see

length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...

* Impact parameter (''b'') * Molality (''b'') * Barn (unit) (b), a unit of area *

Magnetic field A magnetic field is a vector field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular to its own velocity and to ...

(''B'') * Napierian absorbance (''B'') * Rotational constant (''B'') * Second virial coefficient (''B'') *

Susceptance In electrical engineering, susceptance (''B'') is the imaginary part of admittance, where the real part is conductance. The reciprocal of admittance is impedance, where the imaginary part is reactance and the real part is resistance. In SI unit ...

(''B'') * Bel (''B''), a logarithmic unit equal to ten

decibel The decibel (symbol: dB) is a relative unit of measurement equal to one tenth of a bel (B). It expresses the ratio of two values of a power or root-power quantity on a logarithmic scale. Two signals whose levels differ by one decibel have a po ...

Other uses in science, technology, and mathematics

* ''B'', a

modal logic Modal logic is a collection of formal systems developed to represent statements about necessity and possibility. It plays a major role in philosophy of language, epistemology, metaphysics, and natural language semantics. Modal logics extend other ...

* Boolean domain (

\mathbb

), in mathematics *

Boron Boron is a chemical element with the symbol B and atomic number 5. In its crystalline form it is a brittle, dark, lustrous metalloid; in its amorphous form it is a brown powder. As the lightest element of the ''boron group'' it has th ...

, symbol B, a chemical element * Bulb (photography), a shutter-speed setting * B battery, a battery used to provide the plate voltage of a vacuum tube * B horizon, a layer of soil commonly known as subsoil * B, B+ and B−, expressions of buoyancy in convective available potential energy

Linguistics

* В, a letter of the Cyrillic alphabet * Voiced bilabial stop (b, in the International Phonetic Alphabet)

Arts and media

Music

Musical notation

* B (musical note) *

B major B major (or the key of B) is a major scale based on B. The pitches B, C, D, E, F, G, and A are all part of the B major scale. Its key signature has five sharps. Its relative minor is G-sharp minor, its parallel minor is B minor, and its ...

, a scale * B minor, a scale * B major chord, Chord names and symbols (popular music) *

Flat (music) In music, flat (Italian bemolle for "soft B") means "lower in pitch". Flat is the opposite of sharp, which is a raising of pitch. In musical notation, flat means "lower in pitch by one semitone (half step)", notated using the symbol which is deri ...

, a note lower in pitch by a semitone

Performers

Beyoncé Beyoncé Giselle Knowles-Carter ( ; born September 4, 1981) is an American singer, songwriter, and actress. Beyoncé's boundary-pushing artistry and vocals have made her the most influential female musician of the 21st century, according to ...

* B, member of

Superorganism (band) Superorganism are an indie pop band based in London, formed in early 2017. The group originally consisted of eight members: lead vocalist Orono Noguchi, as well as Emily, Harry, Tucan, Robert Strange, Ruby, B, and Soul. Many of the group's memb ...

Recordings

* ''B'' (BamBam EP), an extended play by BamBam * ''B'' (Battles EP), an extended play by Battles * ''B'' (I Am Kloot album), a compilation album by I Am Kloot * ''b'' (Moxy Früvous EP), an extended play by Moxy Früvous * "b", an Iamamiwhoami song * "B", a song by Todrick Hall from his 2018 album '' Forbidden''

Other media

* /b/, a board on 4chan * ''b'' (newspaper), a free daily, tabloid sized newspaper, published by ''The Baltimore Sun'' * ''

Codex Vaticanus Graecus 1209 The Codex Vaticanus ( The Vatican, Bibl. Vat., Vat. gr. 1209), designated by siglum B or 03 (in the Gregory-Aland numbering), δ 1 ( von Soden), is a fourth-century Christian manuscript of a Greek Bible, containing the majority of the Greek Old ...

'', an ancient bible * Rajawali Televisi, previously named B Channel, a television channel in Indonesia * B, the production code for the 1963–64 ''Doctor Who'' serial '' The Daleks'' * B, a character in '' Total Drama: Revenge of the Island'' * '' "B" Is for Burglar'', the second novel in Sue Grafton's "Alphabet mystery" series, published in 1985

Places

* Belgium, on the vehicle registration plates of the European Union * Bucharest, on the vehicle registration plates of Romania

Sport

* Australian rules football positions#Full back, in Australian Rules football * B, often used after the name of football clubs to denote a reserve team

Transportation

* B (New York City Subway service) *

B Line (Los Angeles Metro) The B Line (formerly Red Line from 1993–2020) is a fully underground rapid transit line operating in Los Angeles, running between Downtown Los Angeles and North Hollywood. It is one of seven lines on the Metro Rail system, operated by the L ...

* Line B (Buenos Aires Metro) * B (S-train), in Copenhagen * RER B, a line in the RER of Paris * Bundesstraße (federal highway) in Austria and Germany (abbreviation B) * Bayshore Route of Shuto Expressway in Japan, numbered as route B

Other uses

B (grade) This is a list of grading systems used by countries of the world, primarily within the fields of secondary education and university education, organized by continent with links to specifics in numerous entries. Africa Nigeria The choice of gr ...

, for evaluation of students' work * B (bank), a banking brand in the United Kingdom * Barnabites ( la, Clerici Regulares Sancti Pauli), a religious order abbreviated to the postnominal ''B.'' * Bravo, the military time zone code for UTC+02:00 * Brutus, a Roman cognomen (abbreviation B) * Farmall B, a tractor produced by International Harvester from 1939 to 1947 * Dominical letter B for a

common year starting on Saturday A common year starting on Saturday is any non-leap year (i.e. a year with 365 days) that begins on Saturday, 1 January, and ends on Saturday, 31 December. Its dominical letter hence is B. The current year, 2022, is a common year starting on Saturd ...