Leet (most commonly 1337 but often also leetspeak, l33t5p34k, 133t, or l33t) from the phonetic form of the word "elite", is a cipher, or novel form of English spelling. It is characterized by the use of non-alphabetic characters to stand for letters bearing a superficial resemblance, and by a number of spelling changes such as the substitution of "z" for final "s" and "x" for "(c)k" or "(c)ks." Leetspeak was first traditionally used on bulletin board systems and then later adopted by America Online users and other Internet communities.
However, leetspeak is not popular amongst all hackers, and nowadays is most commonly used in an ironic manner to represent immaturity. Many consider it a pointless affectation, and as it has become widely used it is less useful as a way of showing membership of an "elite" group. It is nonetheless a cultural phenomenon well-known amongst hackers and many other Internet users.
Certain factions maintain that "true" leetspeak is spelled correctly, with the exceptions described above. They do not consider the use of extreme short forms (such as "b" for "be", or "u" for "you") as leetspeak; instead, they refer to it by such terms as "AOL speak". This is because they associate such habits with users who use ISPs like AOL, which is associated with "newbiness" and therefore not considered "elite". Another convention sometimes associated with leetspeak or Internet chatting is capitalizing every other letter (LiKe ThIs), sometimes called studlycaps or stickycaps. A similar habit involves capitalizing every consonant (LiKe THiS).