H is the eighth letter of the Latin alphabet. H may also refer to:

Musical symbols

* H number, Harry Halbreich reference mechanism for music by Honegger and Martinů * H, B (musical note) * H,

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 ...

People

* H. (noble) (died after 1279), an unidentified nobleman in the Kingdom of Hungary who served as master of the horse * H. (1900–1995), British activist and economist Edgar Hardcastle * H (born 1957), British guitarist Adrian Smith * H (born 1976), British singer Ian Watkins (Steps) * h (born 1959), British vocalist Steve Hogarth * H (born 1981/82), one of the attackers in the Sydney gang rapes#Attackers, Sydney gang rapes * H. (born 1925), girl who gave birth to a child when she was List of youngest birth mothers, six years old *H Waldman (born 1972), American-Israeli basketball player

Science and mathematics

* h, hour * h, hecto-, the SI prefix for hundred or 10²

Biology

* Haplogroup H ** Haplogroup H (mtDNA), human mitochondrial DNA ** Haplogroup H (Y-DNA), human Y-chromosome DNA * ATC code H ''Systemic hormonal preparations, excluding sex hormones and insulins'', a section of the Anatomical Therapeutic Chemical Classification System * Fay and Wu's H, a statistical test used in DNA analysis

Chemistry

* Hydrogen, symbol H, a chemical element * H, code for a formulation of sulfur mustard

Computer science

* Language H, procedural programming language * or , suffixed to denote Hexadecimal#Representing hexadecimal, hexadecimal in Intel-derived assembly languages * .h, the filename extension for the C Include directive#C/C++, include directive called header

Linguistics

* , the International Phonetic Alphabet symbol for a voiceless glottal fricative sound * H or high, the high-prestige register in a diglossia

Mathematics

* H, the upper half-plane of the complex numbers * , the Heaviside step function * h, impulse response in LTI system theory * H, system function, system response, or transfer function in LTI system theory

Physics and cosmology

Constants

* h, Planck constant * H, Hubble constant * h, dimensionless Hubble constant

Measures

* H, absolute magnitude in the context of the Solar system * H (as in ), magnitude of enthalpy * h, Convection (heat transfer), convective heat transfer coefficient * H, magnetic field intensity

Other uses in physics

* H, symbol for the Henry (unit), the SI derived unit of inductance * H⁰, the symbol of the Higgs boson

Planets

* H, distortion of symbol for Uranus * h, distortion of symbol for Saturn

Other uses in science

* h-index, an author-level metric of the productivity and citation impact of the publications of a scientist or scholar

Arts and media

Film and TV

* H (1990 film), ''H'' (1990 film), a 1990 Canadian film * H (2002 film), ''H'' (2002 film), a 2002 Korean film * H. (2014 film), ''H.'' (2014 film), a 2014 American film by Rania Attieh and Daniel Garcia * H (TV series), ''H'' (TV series), a 1998-2002 French TV series * H, the production code for the 1964 ''Doctor Who'' serial ''The Reign of Terror (Doctor Who), The Reign of Terror'' * H, a codename used to refer to an anonymous individual in the police procedural drama ''Line of Duty'' * "H", the fifth episode of the sixth series of ''List of Taskmaster episodes#Series 6 (2018), Taskmaster'' that aired in 2018

Music

*''h'', a 1990 compilation album by Hitomi (singer) *''H'', a 1980 album by Bob James (musician) * H (Ayumi Hamasaki EP), ''H'' (Ayumi Hamasaki EP), 2002 * H (Lee Hae-ri EP), ''H'' (Lee Hae-ri EP), 2017 * H. (song), "H." (song), a song by Tool on their 1996 ''Ænima'' album

Other media

*H (magazine), ''H'' (magazine) * Revista H, a monthly Mexican men's magazine * ''"H" Is for Homicide'', the eighth novel in Sue Grafton's "Alphabet mystery" series, published in 1991

Other uses

* Heroin * Н, a letter of the Cyrillic alphabet analogous to N * Һ, letter Shha of the Cyrillic alphabet * Trains: ** H (S-train), a train service in Metropolitan Copenhagen ** H, Rockaway Park Shuttle subway service in New York ** Line H (Buenos Aires Underground), Line H of the Buenos Aires Subte * H, a Hitachi, Ltd. mobile phone * H, Hentai#H or "Etchi", sexual content or activity, associated with Japanese "Hentai" * Hurricane tie, used in construction * Conservative Party of Norway (''Høyre'') * The military designation for helicopters, such as the UH-60 Blackhawk and AH-64 Apache * H, a symbol for a heliport * H, the international license plate code of Hungary * Hit (baseball) * Farmall H, a tractor produced by International Harvester from 1939 to 1953 * Hotel, the List of military time zones#H, military time zone code for UTC+08:00