I is the ninth letter of the Latin alphabet. Its English name ( ) is spelled i.

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 a voiced pharyngeal fricative (/ʕ/) in Egyptian, but was reassigned to /j/ (as in English "yes") 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 /aɪ/, that developed from Middle English /iː/ after the Great Vowel Shift of the 15th century, as well as the "short", open /ɪ/ 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

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

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

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.

In British Sign Language (BSL), the letter 'i' is represented as the extended index of right hand touching the tip of the middle finger on the left hand. Left hand should be open.

See also

• i Egocentric or egocentrism
• И, и - I (Cyrillic)
• Tittle
• Turkish dotted and dotless I