H1

H1, H-1, H01, H I may refer to:

Places

 * Interstate H-1, a highway in Hawaii
 * Area H1, the area of Hebron controlled by the Palestinian Authority under the Hebron Protocol

Science

 * H1 (particle detector)
 * Histamine H1 receptor
 * Histone H1, a protein


 * British NVC community H1, a heath zone
 * Hydrogen atom (H1)
 * Protium (isotope), an isotope of hydrogen
 * H I region, a cloud in the interstellar medium
 * ATC code H01 Pituitary and hypothalamic hormones and analogues, a subgroup of the Anatomical Therapeutic Chemical Classification System
 * Haplogroup H1 (disambiguation), a grouping in genetics based on certain similarities
 * Alternative hypothesis (H1)

Technology

 * , level 1 heading markup for HTML Web pages; see HTML element
 * DSC-H1, a Sony Cybershot digital camera
 * H1, John Harrison's first marine chronometer
 * Tianwen-1 (formerly Huoxing-1), first Chinese space probe to reach Mars
 * H-1NF, the Australian Plasma Fusion Research Facility, formerly H-1 Heliac stellarator

Transportation

 * H1 Lamp, an automotive halogen light bulb
 * H-I or H–1, a Japanese rocket
 * Rocketdyne H-1, a liquid-propellant rocket engine

Aviation

 * Bell Huey family Bell H-1, series of helicopters with that designation
 * Hooters Air airline
 * Hughes H-1 Racer, a racing aircraft

Motor vehicles

 * Haval H1, a Chinese subcompact crossover
 * Hummer H1, an American full-size SUV
 * Hyundai H-1, a South Korean commercial van
 * Tiger H1, a German heavy tank used during WW2

Motorcycles

 * Kawasaki H1 Mach III, road motorcycle
 * Kawasaki H1R, racing motorcycle

Ships

 * HMS H1, a 1915 British Royal Navy H-class submarine
 * HMS Hotspur (H01), a 1935 British Royal Navy H-class destroyer
 * USS H-1, a 1913 United States Navy submarine

Rail

 * LB&SCR H1 class, a class of British steam locomotives
 * LNER Class H1, a class of British steam locomotives
 * Designation for METRORail Siemens S70 light rail vehicles

Time

 * H1 may refer to the first half of the business year, while H2 refers to the second half.

Other uses

 * H1 (classification), a para-cycling classification
 * *h1, one of the three laryngeals in the reconstructed Proto-Indo-European language
 * H1 Unlimited, a premier unlimited hydroplane racing league
 * Hora Um da Notícia, a news program aired by Rede Globo