I is the ninth letter of the Latin alphabet.
I or i may also refer to:
Language
- I (pronoun), the first-person singular subject pronoun in English
- I (Cyrillic), a letter used in almost all ancient and modern Cyrillic alphabets
- ı, dotless I, letter used in Turkish and Azerbaijani
- i, close front unrounded vowel, in the International Phonetic Alphabet
- ɨ, close central unrounded vowel, in the International Phonetic Alphabet
- ɪ, near-close near-front unrounded vowel, in the International Phonetic Alphabet
- I (kana), one of the Japanese kana that each represent one mora
- I, male prefix to some Balinese names
Science, technology, and mathematics
Biology
- Troponin I, one of the three troponins
- Haplogroup I (mtDNA), a human mitochondrial DNA (mtDNA) haplogroup
- Haplogroup I (Y-DNA), a Y-chromosomal DNA (Y-DNA) haplogroup
- Olfactory nerve, the 1st cranial nerve in human anatomy
- the Lợn Ỉ or Vietnamese Pot-bellied pig
Chemistry
- Iodine, symbol I, a chemical element
- I, isoleucine, an amino acid
- I, ionic strength in a chemical solution
- i, Van 't Hoff factor
Computing
i, a common generic index variable often used in program loops<i>, an HTML element for marking italic type.i, the common filename extension for a file that contains the output from a preprocessor- i-, a prefix for Apple products e.g. iMac, iPod, iPhone
- i-, an Internet-related prefix used by Internet and electronic companies
Mathematics
- I, the Roman numeral for 1
- i, imaginary unit, for which i2 = −1
- I or In, identity matrix of indeterminate size (or of size n)
- I, unit interval, which contains all real numbers from 0 to 1 inclusive
- i, an index variable, e. g. in a matrix or for summation
- Ix(a,b), the regularized incomplete beta function (of a variable x and parameters a,b)
- î, the unit vector along the x-axis in Cartesian coordinates
Physics and astronomy
- I, i, electric current
- I, isospin
- I, luminous intensity
- I, moment of inertia
- i, orbital inclination
- I (Roman number one), in the Yerkes spectral classification scheme, the symbol for supergiants
Telecommunication
- I band (NATO), the range of radio frequencies from 8 GHz to 10 GHz in the electromagnetic spectrum
- I, the ITU prefix allocated to Italy in radio communication
- I, in QAM modulation schemes, the in-phase communications channel
Other uses in technology
- i, a suffix unit for video resolution (vertical Interlaced lines), as in 480i or 1080i
- I, in the YIQ colorspace commonly used with the NTSC television encoding scheme, the color-difference channel which is in-phase with the subcarrier
Arts and media
Music
- I (band), a Norwegian heavy metal band
- I, a diatonic function in tonal music theory
Albums
- i (A.R. Kane album), 1989
- I (Ben Lester album), 2019
- I (Cilvaringz album), 2007
- I (Cursed album), 2003
- I (Die Krupps album), 1992
- I (Felix Jaehn album), 2018
- I (Ikimono-gakari album), 2013
- I (Imminence album), 2014
- I (Jaejoong EP), 2013
- I (JonnyX and the Groadies album), 2005
- I (Juju album), 2018
- I (Kingston Wall album), 1992
- I (Kurt Nilsen album), 2003
- i (The Magnetic Fields album), 2004
- I (Meshuggah EP), 2004
- i (Misako Odani album), 1997
- I (Nightingale album), 2000
- I (Sahg album), 2006
- I (Taeyeon EP), 2015
- I (Xerath album), 2009
- I (soundtrack), by A. R. Rahman from the eponymous 2015 film
Songs
- "i" (Kendrick Lamar song), a 2014 song by Kendrick Lamar from his album To Pimp a Butterfly
- "i" (Lil Skies song), a song 2019 by Lil Skies from his debut album Shelby
- "I" (Taproot song), a 2001 song by band Taproot from their album Gift
- "I (Who Have Nothing)", a 1966 Ben. E. King song also recorded by Tom Jones, who used the title for one of his albums
- "I", a 2003 song on Weather Systems, an album by Andrew Bird
- "I", a 1992 song on Selected Ambient Works 85–92, an album by Aphex Twin
- "I", a 1992 song on Dehumanizer, an album by Black Sabbath
- "I", a 1997 song on Coal Chamber, an album by Coal Chamber
- "I", a 1967 song on Underground, an album by The Electric Prunes
- "I", a 2012 song on Muse, an album by Jolin Tsai
- "I", a 1981 song on Music from "The Elder", an album by Kiss
- "I", a 1994 song on Made in USA, an album by Pizzicato Five
- "I", a 1999 song on Eternal, an album by Samael
- "I", a 2003 song on Winter Story, an album by Shinhwa
- "I", a 2008 song on In the Shadow of a Thousand Suns, an album by Abigail Williams
- "I", a 2011 song on Cinderella's Eyes, an album by Nicola Roberts
- "I", a 2015 song on I, an EP by Taeyeon
- "I", a 2016 song by Rezz
- "I", a 2019 song by Hey! Say! JUMP
Other media
- I (2015 film), an Indian Tamil-language film
- I (2016 film), an Iranian film
- i (TV network), the former name of ION Television
- i (newspaper), a British newspaper based in London
- i (Portuguese newspaper), a Portuguese newspaper based in Lisbon
- I, a character in the comic book series Adventure into Fear
- "I" Is for Innocent, the ninth novel in Sue Grafton's "Alphabet mystery" series, published in 1992
- I, a Man, a 1967 Andy Warhol film
Mythology
Vehicles and transportation
- Italy (I), in the list of international vehicle registration codes
- Italy (aircraft registration prefix)
- Mitsubishi i, a Japanese kei car
- I (Los Angeles Railway), a former streetcar line in Los Angeles
- Toei Mita Line, a subway service operated by the Tokyo Metropolitan Bureau of Transportation (Toei), labeled
- Imazatosuji Line, a subway service operated by the Osaka Metro, labeled
, the official West Japan Railway Company service symbol for the Kakogawa Line.
Other uses
- i, an international symbol for visitor or tourist information; see ISO 7001
- Nintendo DSi, the third model in the Nintendo DS line, released in 2008
- Nintendo DSi XL, the larger version of the DSi, released in 2009
- I, an alternative romanization of Lee (Korean surname)
- I-Foundation, a charity in charge of state-funded Hindu faith schools in the United Kingdom
- Interest rate (i), in economics
- Investment (I), in economics
- India, the military time zone code for UTC+09:00
See also
Search for "i" on Wikipedia.