I (disambiguation)

I is the ninth letter of the Latin alphabet.

I or i can also refer to:

Language

• I (pronoun), the first-person singular subject pronoun in English

Vowels

• the Close front unrounded vowel in the International Phonetic Alphabet and many other Latin-based orthographies
• /i/, /ɨ/ and /ɪ/, in the International Phonetic Alphabet, three vowels represented by variations of the letter I
• I (kana), one of the Japanese kana that each represent one mora

Anatomy

• Olfactory nerve, 1st cranial nerve

Mathematics

• I, 1 (number) in Roman numerals
• i, the imaginary unit for which i² = −1 (see also imaginary number)
• I (or I_n), an identity matrix of indeterminate size (or of size n)
• i, an index variable in a matrix
• I_x(a,b), the regularized incomplete beta function (of a variable x and parameters a,b)
• I, the closed unit interval which contains all real numbers from 0 to 1 inclusive
• ${\hat{\imath}}$ (pronounced "i-hat"), the unit vector along the x-axis in Cartesian coordinates

Physics

• I and i, symbols for electric current signals in electronic engineering
• I, the moment of inertia
• I, symbol for the luminous intensity
• i, symbol for the van't Hoff factor or coefficient

Astronomy

• i, the symbol for orbital inclination
• I, in the Yerkes spectral classification scheme the symbol for supergiants

Chemistry

• I, the symbol for iodine on the periodic table
• I, the symbol for isoleucine in biochemistry

Genetics

• Haplogroup I (mtDNA), a human mitochondrial DNA (mtDNA) haplogroup
• Haplogroup I (Y-DNA), a Y-chromosomal DNA (Y-DNA) haplogroup

Economics

• i, the symbol for the interest rate
• I, the symbol for investment

Computers

• i, a common generic index variable often used for looping constructs
• <i>, an HTML element for marking italic type
• .i, the common filename extension for a file that contains the output from a preprocessor.
• IBM i is a computer operating system
• Many Apple products are known by i[Blank], e.g. iMac, iPod, iPhone.
• Lowercase i prefix, a common prefix used by Internet and electronic companies

Music

• I, a diatonic function in tonal music theory
• I (band), a band formed by members of Immortal, Enslaved, Gorgoroth, and Sahg

Albums

• I (Kurt Nilsen album)
• i (The Magnetic Fields album)
• I (Cilvaringz album)
• I (Die Krupps album)
• I (JonnyX and the Groadies album)
• i (Misako Odani album)
• I (Nightingale album)
• I (EP), an EP by Meshuggah

Songs

• "I" (Aphex Twin song)
• "I", a song on Dehumanizer, an album by Black Sabbath
• "I", a song on Weather Systems, an album by Andrew Bird
• "I", a song on Coal Chamber, an album by Coal Chamber
• "I", a song on Music from "The Elder", an album by KISS
• "I", a song on Eternal, an album by Samael
• "I (Who Have Nothing)", a Ben. E. King song also recorded by Tom Jones, who used the title for one of his albums

Media

• i, a suffix unit for video resolution (vertical Interlaced lines), as in 480i or 1080i
• i (TV network), the former name of ION Television
• I band, 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
• I, in the YIQ colorspace commonly used with the NTSC television encoding scheme, the color-difference channel which is in-phase with the subcarrier
• i (newspaper), a British newspaper.
• i, in lower case on a blue field, the international symbol for visitor or tourist information; (see ISO 7001)

Individuals

• I, a character in Adventure into Fear who acted as a guide for Morbius, the Living Vampire
• Goddess I, a Mayan deity

Vehicles

• I, the symbol for Italy in the list of international license plate codes
• I, the registration prefix for Italy in aircraft registrations
• Mitsubishi i, a Japanese kei car

See also

• All pages beginning with "I"
• All pages with titles containing "I"