. . . it was used in a sort of sub-text that is included in coding so that hackers who send lines of code to each other would know what it did while others would not.
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n: a language originally created by computer hackers to communicate through their coding while others could not do such a thing. It misspells words that have been commonly misspelled in English, such as "Teh". It also spells most words phonetically, making it as easy to type in leet as possible. When a word ends in "X" or "cks", it is suitable to put an "orz" at the end. . . leet is also a very flexable language, so you can make your own words and modify the English language (teh smecks is a common substitute for sexy) in any way you see fit as long as it's close.
adj: superior; elite.
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n: 1 |2 1337 (Direct translation: I r leet. English: I am elite.)
adj: That dude's so leet!
http://www.urbandictionary.com/define.php?term=leet