Online Language. Because the standardised version has been lost or ignored or never invented, many dialects have appeared. While there is grammatical and spelling differences, it is almost identical to English to the point of being a mere substitution alphabet, and is rarely used in other languages.
-Note: The only "Common" themes are that 4=A, 6=G, 7=T, 5=S, 3=E and 0=O. The letter F does not exist in most L337. While l= "exists", you'll look like an idiot using it instead of pl-l (or any other letter for H).
l)0l\l'+ pl-lu(l< up 7l-l!5 l4l\l6l_l463. u53 !+ l235p0l\l54bl3.