The letter J is the tenth of the Latin alphabet; it was the last to be added to that alphabet.

History

J was originally a capital of I. Some people in the German-speaking world still follow the convention of writing (for example) "Isabel" as "Jsabel" and Jnes as "Ines"; one also sometimes encounters J as a capital of I in Italy.

Petrus Ramus (d. 1572) was the first to make a distinction between I and J. Originally, both I and J were pronounced (see IPA) as , [i:], and [j]; but Romance languages developed new sounds (from former [j] and [g]) that came to be represented as I and J; therefore, English J (from French J) has a sound quite different from I.

In other Germanic languages J stands for [j]. This is also true of Slavic languages that use the Latin alphabet as well as in Hungarian, Albanian, and Finnish, where it can never be a fricative.

In modern standard Italian only foreign or Latin words have J. Until the 19th century, J was used instead of I in diphthongs, as a replacement for final -ii, or in vowels groups (as in Savoja); this rule was quite strict for official writing. J is also used for rendering words in dialect, where it stands for [j], e.g. Romanesque ajo for standard aglio (garlic).

In Spanish J stands for [x ~ h] (which in some cases developed from the [dʒ] sound, i.e. the same sound that English still has). In French former dʒ is now pronounced as [ʒ] (as in English measure).

In Turkish, Azeri and Tatar J is always prounced [ʒ].

Hebrew also influenced the English J, which in a few cases is used for [j] in place of the more normal Y. The classic example is Hallelujah which is pronounced the same as Halleluyah. See the Hebrew yod for more details.

Alternate representations

Juliet represents the letter J in the NATO phonetic alphabet.

In international Morse code the letter J is DitDahDahDah: · - - -

In Braille the letter J is represented as ⠚ (in Unicode), the dot pattern,

.X
XX
..

Meanings for J

J can also refer to:

• an abbreviation for the months of January, June, and July;
• the imaginary unit (), in fields such as physics and electrical engineering where i is traditionally used to denote a changing current);
• one of the three imaginary units of quaternions;
• the joule, the SI derived unit for energy;
• one of the two names of the J/Psi particle in high-energy physics;
• an abbreviation for the Jehovist or Yahwist source, in the documentary hypothesis of the Hebrew Bible;
• the jack in a deck of playing cards;
• a spliff (i.e. an abbreviation for "joint"); and
• J Records, a record label.

Regional meanings

• the international licence plate code for Japan;
• As the first letter of a postal code in Canada, J is used for the western and northern regions of Quebec;
• On the New York City Subway system, J is a rapid transit service running from Downtown Manhattan to Jamaica, Queens.

Computing

In Unicode the capital J is codepoint U+004A and the lowercase j is U+006A.

The ASCII code for capital J is 74 and for lowercase j is 106; or in binary 01001010 and 01101010, correspondingly.

The EBCDIC code for capital J is 209 and for lowercase j is 145.

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

A capital J can refer to the J programming language.

See also

• J circumflex (Ĵ) in Esperanto orthography