A parent's primer to computer slang
Here is a gem of an article from Microsoft:
Key points for learning leetspeek
- Numbers are often used as letters. The term "leet" could be written as "1337," with "1" replacing the letter L, "3" posing as a backwards letter E, and "7" resembling the letter T. "0" (zero) will typically replace the letter "O."
- Characters of similar appearance can be used to replace the letters they resemble. For example, "5" or even "$" can replace the letter S. Applying this style, the word "leetspeek" can be written as "133t5p33k" or even "!337$p34k," with "4" replacing the letter A.
- Letters can be substituted for other letters that may sound alike. Using "Z" for a final letter S, and "X" for words ending in the letters C or K is common. For example, leetspeekers might refer to their computer "5×1llz" (skills).
- Rules of grammar are rarely obeyed. Some leetspeekers will capitalize every letter except for vowels (LiKe THiS) and otherwise reject conventional English style and grammar.
- Mistakes are often uncorrected. Common typing misspellings (or typos) such as "teh" instead of "the" are left uncorrected and may be adopted to replace the correct spelling.
Full text is here.