I (disambiguation)

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
Close front unrounded vowel (i), in the International Phonetic Alphabet
Close central unrounded vowel (ɨ), in the International Phonetic Alphabet
Near-close near-front unrounded vowel (ɪ), in the International Phonetic Alphabet
I (kana), one of the Japanese kana that each represent one mora
I, male prefix to some Balinese names

1 (number) (Roman numeral: I)
Imaginary unit (i), for which i² = −1
- Imaginary number
Identity matrix ( $I$ or $I n$ ), of indeterminate size (or of size $n$ )
Unit interval ( $I$ ), which contains all real numbers from 0 to 1 inclusive
$i$ , an index variable in a matrix
$I x (a, b)$ , the regularized incomplete beta function (of a variable x and parameters a,b)
$î$ , the unit vector along the x-axis in Cartesian coordinates
i, the index of summation, used to calculate a sum

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
IBM i, a computer operating system
i-, a prefix for Apple products e.g. iMac, iPod, iPhone
i-, an Internet-related prefix used by Internet and electronic companies

"I" (Kendrick Lamar song)
"I" (Taproot song)
"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 song on Weather Systems, an album by Andrew Bird
"I", a song on Selected Ambient Works 85–92, an album by Aphex Twin
"I", a song on Dehumanizer, an album by Black Sabbath
"I", a song on Coal Chamber, an album by Coal Chamber
"I", a song on Underground, an album by The Electric Prunes
"I", a song on Music from "The Elder", an album by Kiss
"I", a song on Eternal, an album by Samael
"I", a song on Muse, an album by Jolin Tsai
"I", a song on Winter Story, an album by Shinhwa
"I", a song on I, an EP by Taeyeon

I (film), a 2015 Tamil language Indian film
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 (Portuguese newspaper), a Portuguese newspaper
i, the international symbol for visitor or tourist information; see ISO 7001

I-Foundation, a Hindu and ISKCON charity in charge of state-funded Hindu faith schools in the United Kingdom
Interest rate (i), in economics
Investment (I), in economics