I is the 9th letter in the Latin alphabet.
History
The letter I derived from the Greek iota (Ι, ι). It stood for the vowel /i/, the same as in the Old Italic alphabet. In Latin (as in Modern Greek) /j/ (as English Y in YOKE) was added. In Semitic, /j/ was the usual sound value of Jôd (probably originally a pictogram for an arm with hand), /i/ only in foreign words.
In English, I represents different sounds, among them a diphthong that developed from /i:/ as well as short, open /I/ as in BILL. The dot over the lowercase 'i' is 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.
Alternate representations
India represents the letter I in the NATO phonetic alphabet.
In international Morse code the letter I is DitDit: · ·
In Braille the letter I is represented as ⠊ (in Unicode), the dot pattern,
.X
X.
..
Computing
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 biochemistry, I is the symbol for isoleucine.
- In chemistry, I is the symbol for iodine.
- In computing,
<i>
is the HTML tag for marking italic type. It is also commonly used as the name of the index variable in for loops when no other name suggests itself.
- In English, I is a pronoun denoting the first person, singular.
- In international licence plate codes, I stands for Italy.
- In mathematics,
- In physics and electronic engineering, I is often the variable for electric current. The imaginary unit is represented by j instead.
- In radiocommunication, I is the ITU prefix allocated to Italy.
- In Roman numerals, I denotes the number 1.
- In structural engineering I is used for the moment of inertia
- In music,
- In economics, I is usually used to represent investment.
See also
Ì, Í, Î, Ï, Ĭ, İ