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Encyclopedia : I : I : I : I

Latin alphabet
	Aa	Bb	Cc	Dd
Ee	Ff	Gg	Hh	Ii	Jj
Kk	Ll	Mm	Nn	Oo	Pp
Qq	Rr	Ss	Tt	Uu	Vv
	Ww	Xx	Yy	Zz

The lowercase "i" redirects here. This article is about a letter. For other uses, see I (disambiguation).

''Due to MediaWiki's uppercase algorithm, ı, the lowercase dotless i, redirects here.

The letter I is the ninth letter in the Latin alphabet. Its English name is pronounced [aɪ].

Contents

1 History
2 Codes for computing
3 Meanings for I

3.1 Use in Germany

4 See also

History

	Proto-Semitic Y	Phoenician Y	Etruscan I	Greek Iota
D36

In Semitic, the letter Yôdh was probably originally a pictogram for an arm with hand, derived from a similar hieroglyph that had the value of /ˁ/ in Egyptian, but was reassigned to /j/ (pronounced as English Y in "yoke") by Semites, because their word for "arm" began with that sound. This letter could also be used for the vowel sound /i/, mainly in foreign words.

The Greeks adopted a form of this Phoenician yodh as their letter iota (Ι, ι). It stood for the vowel /i/, the same as in the Old Italic alphabet. In Latin (as in Modern Greek), it was also used for the consonant sound of /j/. The modern letter J was originally a variation of this letter, and both were interchangeably used for both the vowel and the consonant, only coming to be differentiated in the 16th century.

In modern English, I represents different sounds, mainly a "long" diphthong /ai/, that developed from /i:/ during the Great vowel shift of the 15th century, as well as the "short", open /I/ as in "bill". The dot over the lowercase 'i' is sometimes called a tittle. In the Turkish alphabet, dotted and dotless I are considered separate letters and both have uppercase (I, İ) and lowercase (ı, i) forms.

Codes for computing

Alternative representations for

NATO phonetic		Morse code
India		[··]

Signal flag	Semaphore	ASL Manual	Braille

In Unicode the capital I is codepoint U+0049 and the lowercase i is U+0069.

The ASCII code for capital I is 73 and for lowercase i is 105; or in binary 01001001 and 01101001, correspondingly.

The EBCDIC code for capital I is 201 and for lowercase i is 137.

The numeric character references in HTML and XML are "I" and "i" for upper and lower case respectively.

Meanings for I

In astronomy, i stands for the orbital inclination.
In biochemistry, I is the symbol for isoleucine.
In chemistry, I is the symbol for iodine.
In computing, <i> is a deprecated HTML tag for marking italic type.
In English, I is the nominative case of the pronoun denoting the first person, singular. See [[Wiktionary:I]].
In Economics, I stands for investment.
In international licence plate codes, I stands for Italy.
In the International Phonetic Alphabet, the letter I appears in three forms; its lowercase version, /i/, refers to the close front unrounded vowel; its barred version, /ɨ/, stands for the close central unrounded vowel; and its small capital version, /ɪ/, represents the near-close near-front unrounded vowel.
In mathematics,
* i denotes the imaginary unit, a complex number whose square is equal to −1.
* I denotes the closed unit interval, which contains all real numbers from 0 to 1, inclusive
* I denotes the identity matrix.
* I may denote the value of an integral one is trying to evaluate.
* i is commonly used as an index variable to coordinate vectors or matrices. It is written as a subscript after the indexed element. When used with matrices, it usually indexes rows, in which case columns are usually indexed by j.
In physics and electronic engineering:
* I is used as the symbol representing moment of inertia.
* I is often the variable for electric current. Sometimes both I and i are used for static and small signal respectively. Therefore the imaginary unit is represented by j instead.
* In QAM modulation schemes, I is used to refer to the in-phase communications channel.
In the YIQ colorspace commonly used with the NTSC television encoding scheme, I is the color-difference channel which is in-phase with the subcarrier.
In programming, i is often used as a generic index variable for looping constructs.
In radiocommunication, I is the ITU prefix allocated to Italy.
In Roman numerals, I denotes the number 1 (there are also separate Unicode characters for this number, 0x2160 "Ⅰ" and 0x2170 "ⅰ").
In structural engineering I is used for the moment of inertia
In music,
*the Roman numeral I is the tonic scale degree, chord, or diatonic function, when distinguished I = major and i = minor.
* I is the name of the winner of the Norwegian version of Pop Idol and also World Idol, Kurt Nilsen's debut album. See I (album).
* i is the name of an album by The Magnetic Fields.
* i is the name of a Portuguese post-rock band
* I is the name of a song and EP by Swedish tech metal band, Meshuggah.
In television, i is the television network formerly known as PAX

Use in Germany

In Germany, Roman numerals are often used for numbering. When listing things by capital letters of the alphabet, they avoid using the letter I, skipping over to J, to avoid confusion with the alternative Roman numberal numbering system. For example, in every regiment in the German Army there is what would be expressed in English as a "J company" but no "I company."

I

History

Codes for computing

Meanings for I

Use in Germany

See also